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                                                                   EXHIBIT 10.43

                                 PROMISSORY NOTE

$117,000,000                                                   November 18, 2004
                                                          Boston, Massachusetts

     FOR VALUE RECEIVED, FVE ACQUISITION INC., a Delaware corporation ("MAKER"),
by this promissory note (this "NOTE"), hereby promises unconditionally to pay to
SENIOR HOUSING PROPERTIES TRUST, a Maryland real estate investment trust
("LENDER"), or order, on the 30th day after the date of this Note (the "MATURITY
DATE"), unless sooner paid or payable as herein provided, the principal sum of
ONE HUNDRED SEVENTEEN MILLION DOLLARS ($117,000,000), or so much thereof as
shall be advanced and remain unpaid hereunder, and to pay interest on the
principal sum remaining unpaid hereunder from time to time from the date hereof
until the principal shall have been paid in full.

     1.     BASE INTEREST; TERMS OF PAYMENT.

            (a)     The unpaid principal balance hereof shall bear interest
("BASE INTEREST") from the date of this Note until paid at the Base Interest
Rate (this and other capitalized terms used and not otherwise defined herein
having the meanings ascribed to such terms in SECTION 10). All such interest
shall be calculated on the basis of a 360-day year consisting of twelve (12)
equal 30-day months, with partial months calculated on the basis of the actual
number of days elapsed.

            (b)     Base Interest shall be due and payable on the Maturity Date
or if sooner, on the date of prepayment pursuant to Section 4 or on
acceleration.

     2.     LATE FEE. If any payment required to be made to Lender hereunder
shall not be paid within ten (10) days after the date the same becomes due,
Maker shall, at the election of Lender, pay to Lender, in addition to all other
amounts payable hereunder and not as a penalty but as the agreed cost to Lender
resulting from such delay, a "late fee" equal to five percent (5%) of such
overdue amount.

     3.     DEFAULT RATE. From and after the occurrence and during the
continuance of an Event of Default, all amounts due and unpaid hereunder shall,
to the extent permitted by law, bear

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interest until paid, at the Default Rate; such interest shall be calculated on
the basis of a 360-day year consisting of twelve equal 30-day months, with
partial months calculated on the basis of the actual number of days elapsed.

     4.     PREPAYMENT. Contemporaneously with the sale of the Facilities to one
or more subsidiaries of Lender, Maker shall prepay the unpaid principal of this
Note, together with interest accrued thereon, but without payment of any
prepayment fee, penalty or cost.

     5.     IMPOSTS. Maker shall pay principal, interest and other amounts
under, and in accordance with the terms of, this Note, free and clear of, and
without deduction for, any and all present and future taxes, levies, imposts,
deductions, charges, withholdings, and all liabilities with respect thereto,
excluding income and franchise taxes payable by Lender to the United States of
America or any political subdivision thereof. In addition, Maker shall pay any
federal, state or local taxes on the acquisition of this Note by Lender and any
stamp or other taxes levied by any jurisdiction on the execution, delivery,
registration, performance and enforcement of this Note.

     6.     PLACE AND MANNER OF PAYMENT. All payments of principal, interest and
other amounts payable on or in respect of this Note or the indebtedness
evidenced hereby shall be made to such account of Lender within the continental
United States of America as Lender shall from time to time designate in writing
not less than one (1) business day in advance, in lawful money of the United
States of America, in immediately available Federal funds.

     7.     COLLECTION OF COSTS. Should the indebtedness evidenced by this Note
or any part thereof be collected by action at law, or in bankruptcy,
receivership or other court proceedings, or should this Note be placed in the
hands of attorneys for collection after default, Maker agrees to pay, upon
demand by Lender, in addition to principal and interest and other sums, if any,
due and payable hereon, court costs and reasonable attorneys' fees and other
reasonable collection charges, unless prohibited by law.

     8.     EVENTS OF DEFAULT. If any of the following events (each, an "EVENT
OF DEFAULT") shall have occurred:

     (a)    Maker fails to pay any principal of or interest on this Note when
and as the same shall become due and payable,

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whether at the Maturity Date, upon prepayment pursuant to Section 4, by
acceleration or otherwise; or

            (b)     Maker is generally not paying its debts as such debts become
due or admits in writing that it is not able to pay its debts as such debts
become due or otherwise becomes insolvent; or files, or consents by answer or
otherwise to the filing against it of, a petition for relief or reorganization
or arrangement or any other petition in bankruptcy, for liquidation or to take
advantage of any bankruptcy or insolvency law of any jurisdiction; or makes an
assignment for the benefit of its creditors; or consents to the appointment of a
custodian, receiver, trustee or other officer with similar powers with respect
to it or with respect to any substantial part of its property; or

     (c)    a petition for relief or reorganization or arrangement or any other
petition in bankruptcy, for liquidation, dissolution or winding up of Maker or
for the appointment of a custodian, receiver, trustee or other officer with
similar powers with respect to it or with respect to any substantial part of its
property to take advantage of any bankruptcy or insolvency law of any
jurisdiction is filed against Maker without its consent or other acquiescence
and such petition is not dismissed within 60 days;

then the entire unpaid principal of this Note, together with interest and other
amounts, if any, due hereon, shall in the case of clause (c) or (d) above, or
may at Lender's option in the case of clause (a) above, become immediately due
and payable (if not previously due and payable), without presentation, protest
or notice of any kind.

     9      WAIVER BY BORROWER. To the fullest extent permitted by applicable
law, Maker hereby absolutely and irrevocably waives presentment, demand, notice,
protest, and all other demands, notices and suretyship defenses generally, in
connection with the delivery, acceptance, performance, default or enforcement of
or under this Note.

     10.    DEFINITIONS. For all purposes of this Note, except as otherwise
expressly provided or unless the context otherwise requires, (a) the terms
defined in this section shall have the meanings assigned to them in this section
and include the plural as well as the singular, (b) all references in this Note
to designated "Sections" and other subdivisions are to the designated Sections
and other subdivisions of this Note, and (d) the words "herein," "hereof,"
"hereunder" and other words of

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similar import refer to this Note as a whole and not to any particular Section
or other subdivision.

     (a)    "BASE INTEREST RATE" shall mean eight percent (8%) per annum.

     (b)    "DEFAULT RATE" shall mean the lesser of eighteen percent (18%) per
annum and the maximum rate permitted under applicable law.

     (d)    "EVENT OF DEFAULT" shall have the meaning given such term in
Section 8 of this Note.

     (e)    "FACILITY" the assisted living properties identified in Exhibit A
attached hereto.

     (e)    "MATURITY DATE" shall have the meaning given such term in the first
paragraph of this Note.

     11.    RIGHTS OF LENDER. The rights and remedies of Lender shall be
cumulative and concurrent, and may be pursued singly, successively, or together
in any order against Maker, all at the sole discretion of Lender. None of the
provisions hereof, and none of the rights or remedies of Lender hereunder on
account of any past or future defaults, shall be deemed to have been waived by
Lender's acceptance of any past due amount or by any indulgence granted by
Lender.

     12.    NOTICES. All notices and other communications which by any provision
of this Note are required or permitted to be given shall be given in writing and
shall be sent by express mail, postage prepaid, by recognized courier service or
personally delivered to the receiving party. All such notices and communications
shall be mailed, sent or delivered as follows:

            (a) If to Borrower:

                   FVE Acquisition Inc.
                   c/o Five Star Quality Care, Inc.
                   400 Centre Street
                   Newton, MA  02458

            (b) If to Lender:

                   Senior Housing Properties Trust
                   400 Centre Street
                   Newton, MA  02458

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or to such other person(s) or address(es) as the party to receive any such
communication or notice may have designated by written notice to the other
party.

     13.    RELATIONSHIP. Notwithstanding any provision of this Note regarding
the determination and payment of amounts due and payable hereunder, it is
expressly understood and agreed by Maker and Lender that the relationship
between Maker on the one hand and Lender on the other hand shall be solely that
of debtor to creditor and not that of joint venturers, partners, tenants in
common or joint tenants.

     14.    LIMITATION ON INTEREST. All agreements between Maker and Lender
contained herein are hereby expressly limited so that in no contingency or event
whatsoever, whether by reason of acceleration of maturity of this Note, or
otherwise, shall the amount paid or agreed to be paid to Lender for the use,
forbearance or detention of the principal of this Note exceed the maximum
permissible under applicable law, the benefit of which may be asserted by Maker
as a defense, and if, from any circumstance whatsoever, fulfillment of any
provision of this Note, at the time performance of such provision shall be due,
shall involve transcending the limit of validity prescribed by law, or if from
any circumstances Lender should ever receive as interest under this Note, such
an excessive amount, then, IPSO FACTO, the amount which would be excessive
interest shall be first prorated, spread and allocated, to the fullest extent
permitted by law, to such period and principal as will cause such amount to
conform to and comply with applicable law, and the balance, if any, shall be
applied to the reduction of the principal of this Note and not to the payment of
interest. This provision shall control every other provision of this Note and
all other agreements and instruments between Maker and Lender relative hereto.

     15.    HOLDER. As used herein, the term "Lender" shall mean, in addition to
the initial payee hereof, each person from time to time who is an endorsee of
this Note or the bearer, if this Note is at the time payable to bearer.

     16.    GOVERNING LAW. Except as to matters regarding the internal affairs
of Lender and issues of or limitations on any personal liability of the
shareholders and trustees of Lender for obligations of Lender, as to which the
laws of the State of Maryland shall govern, this Note shall be interpreted,
construed, applied and enforced in accordance with the laws of The Commonwealth
of Massachusetts applicable to contracts between residents of Massachusetts
which are to be performed

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entirely within Massachusetts, regardless of (a) where this Note is executed or
delivered; or (b) where any payment or other performance required by this Note
is made or required to be made; or (c) where any breach of any provision of this
Note occurs, or any cause of action otherwise accrues; or (d) where any action
or other proceeding is instituted or pending; or (e) the nationality,
citizenship, domicile, principal place of business, or jurisdiction of
organization or domestication of any party; or (f) whether the laws of the forum
jurisdiction otherwise would apply the laws of a jurisdiction other than The
Commonwealth of Massachusetts; or (g) any combination of the foregoing.

     To the maximum extent permitted by applicable law, any action to enforce,
arising out of, or relating in any way to the provisions of this Note may be
brought and prosecuted in such court or courts located in The Commonwealth of
Massachusetts as is provided by law; and the parties consent to the jurisdiction
of said court or courts located in The Commonwealth of Massachusetts and to
service of process by registered mail, return receipt requested, or by any other
manner provided by law.

     17.    NON-LIABILITY OF TRUSTEES. THE DECLARATION OF TRUST ESTABLISHING
SENIOR HOUSING PROPERTIES TRUST, A COPY OF WHICH, TOGETHER WITH ALL AMENDMENTS
THERETO (THE "DECLARATION"), IS DULY FILED WITH THE DEPARTMENT OF ASSESSMENTS
AND TAXATION OF THE STATE OF MARYLAND, PROVIDES THAT THE NAME "SENIOR HOUSING
PROPERTIES TRUST " REFERS TO THE TRUSTEES UNDER THE DECLARATION COLLECTIVELY AS
TRUSTEES, BUT NOT INDIVIDUALLY OR PERSONALLY, AND THAT NO TRUSTEE, OFFICER,
SHAREHOLDER, EMPLOYEE OR AGENT OF LENDER SHALL BE HELD TO ANY PERSONAL
LIABILITY, JOINTLY OR SEVERALLY, FOR ANY OBLIGATION OF, OR CLAIM AGAINST,
LENDER. ALL PERSONS DEALING WITH LENDER, IN ANY WAY, SHALL LOOK ONLY TO THE
ASSETS OF LENDER FOR THE PAYMENT OF ANY SUM OR THE PERFORMANCE OF ANY
OBLIGATION.

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     WITNESS the execution hereof under seal as of the date above first written.

                                        FVE ACQUISITION INC.


                                        By:  /s/ Bruce J. Mackey Jr
                                             ---------------------------------
                                             Bruce J. Mackey Jr.
                                             Treasurer and Chief Financial
                                             Officer

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                                    EXHIBIT A

   [This exhibit has been omitted and will be supplementally furnished to the
                Securities and Exchange Commission upon request.]

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