Federal Benefits Equality Act - Declares that, in determining the meaning of any Act of Congress: (1) "marriage" includes a marriage, domestic partnership, civil union, or any other similar legal union between two individuals that is recognized by a state, the District of Columbia, a territory or possession of the United States, or a federally recognized Indian tribe; and (2) "spouse" refers to either member of such a legal union. (Currently, "marriage" is defined only as a legal union between one man and one woman as husband and wife, while "spouse" refers only to a person of the opposite sex who is a husband or wife.)