Bad Dreams (1988)

In the mid-'70s, a cult group called Unity Field commits mass suicide, but a young girl survives. After being in a coma for thirteen years she wakes up in a psyche ward, not remembering the incident. The psychiatrist tries to help her remember, but she begins seeing the leader of the cult talking to her from the grave, and the other members of her therapy group begin to commit suicide around her. Or is it suicide?