Denial

Denial is a 1990 American drama film, written and directed by Erin Dignam. The film features Robin Wright as Sara, a sometime actress, and tall, dark, handsome loner Michael, as lovers. Michael inhabits the realm of obsessional love with Sara becoming his sickness, as he calls it—or her. The film premiered January 21, 1990 at the Sundance Film Festival.

Synopsis from Wikipedia, CC BY-SA 4.0. Everything below written here.