Oh, the Guilt.

Sara awakens one morning to find that her best friend, Jean, has been killed in a car crash. Weeks later, suffering from insomnia and survivor's guilt, Sara begins taking a powerful prescription sleep aid. However, the medication causes her to experience a series of vivid dreams in which she meets with Jean - only this version of Jean is middle-aged and insistent that she survived...and Sara perished. Initially, Sara doubts that the woman is Jean, but soon becomes convinced that she speaks the truth. This prompts a need for Sara to find proof in her waking world that her friend is actually visiting her in dreams and not merely a drug-induced hallucination. Sara spends the remainder of the film attempting to prove that somehow, somewhere, Jean is still alive.