Inner Sanctum(1991)

Overview:

A woman attempts suicide when she suspects her husband doesn't love her and is having an affair. Now she's wheelchair-bound, and her husband, who indeed doesn't love her and is having an affair, hires a private nurse to look after his wife. The nurse begins to suspect that she was hired because of unproven allegations that she murdered someone's wife in a similar situation, that the husband wants her to murder his wife.