The government not only can, but must decide the requirements necessary to receive Medicare benefits. It must also define the terms used in the laws. Whenever “marriage” appears in fed law, it refers to man/woman.
From DOMA: “In determining the meaning of any Act of Congress, or of any ruling, regulation, or interpretation of the various administrative bureaus and agencies of the United States, the word ‘marriage’ means only a legal union between one man and one woman as husband and wife, and the word ‘spouse’ refers only to a person of the opposite sex who is a husband or a wife.”
It is preposterous to let judges define the terms used in federal law. It violates the very separation of powers defined in our Constitution to acquiesce.