The Lady Forgets (1989)

A woman is mugged and bumps her head. To her surprise, when she returns home she finds out that she's been gone for two years and her husband has gotten a divorce in her absence. Searching for an answer to the missing two years, she revisits her old haunts, including her old teaching job, but haunted by dreams of a violent incident she witnessed at an art gallery she is drawn into the intrigues of her other life living with an artist. Meanwhile several men pursue her with deadly intent.