I understand New York to apply the "doctrine of necessities" to hold one spouse responsible for the other spouse's necessary medical care when she cannot pay for her care from her own separate resources and the extension of care was predicated upon the other spouse's credit; but even if that's the case you can attempt to defend against or reduce the claim based upon hardship or inability to pay.
Quote Quoting Promenade Nursing Home, Inc v. Lacey, 814 N.Y.S.2d 564, 10 Misc. 3d 1066A (2005)
A cause of action for medical necessaries, however, is only viable if the primary debtor... is unable to satisfy the debt out of his own resources. (See Gilberg v Lennon, 212 A.D.2d 662, 622 N.Y.S.2d 962 [1st Dept 1995]; Medical Bus Assocs v Steiner, 183 A.D.2d 86, 588 N.Y.S.2d 890 [2d Dept 1992].) In addition, the doctrine of necessaries requires a showing that the necessaries were furnished based on the credit of the spouse and a showing that the amounts alleged to be owed are commensurate with the spouse's means. (See Our Lady of Lourdes Memorial Hospital, Inc. v Frey, 152 A.D.2d 73, 548 N.Y.S.2d 109 [3rd Dept 1989].)