Notwithstanding anything to the contrary in the criteria being used by the Commissioner of Social Security in determining when a husband and wife are to be considered two eligible individuals for purposes of this subchapter and when they are to be considered an eligible individual with an eligible spouse, the State agency administering or supervising the administration of a State plan under any other program under this chapter may (in the administration of such plan) treat a husband and wife living in the same medical treatment facility described in paragraph (1)(B) as though they were an eligible individual with his or her eligible spouse for purposes of this subchapter (rather than two eligible individuals), after they have continuously lived in the same such facility for 6 months, if treating such husband and wife as two eligible individuals would prevent either of them from receiving benefits or assistance under such plan or reduce the amount thereof.