A memo from the USCIS on November 18 2015 clarifies what happens to the Beneficiary when a petition US citizen spouse dies before 2 years of the marriage.

SUBJECT: Approval of a Spousal Immediate Relative Visa Petition under Section 204(l) of the Immigration and Nationality Act after the Death of a U.S. Citizen Petitioner
Revision to Adjudicator’s Field Manual Chapter 10.21(a), (b), (c)(2) and the last paragraph of (c)(5) (AFM Update AD-15-02) to implement Williams v. DHS Secretary, 741 F.3d 1228 (11th Cir. 2014)

Purpose
The Policy Memorandum (PM) revises chapter 10.21(a), (b), (c)(2) and the last paragraph of (c)(5) of the Adjudicator’s Field Manual (AFM) to implement the decision in Williams v. DHS Secretary, 741 F.3d 1228 (11th Cir. 2014) for all spousal immediate relative visa petitions under section 204(l) of the Immigration and Nationality Act (INA) after the death of a U.S. citizen petitioner, including petitions filed outside the jurisdiction of the U.S. Court of Appeals for the Eleventh Circuit (11th Circuit court). This PM partially supersedes PM-602-0017, Approval of Petitions and Applications after the Death of the Qualifying Relative under New Section 204(l) of the Immigration and Nationality Act.

Unless specifically exempted herein, this PM applies to and is binding on all U.S. Citizenship and Immigration Services (USCIS) employees.
Authority INA 204(l) Williams v. DHS Secretary, 741 F.3d 1228 (11th Cir. 2014)

Approval_of_a_Spousal_Immediate_Relative_Visa_Petition