Scared Stiff (1987)

Kate's a single mom rock star recovering from a nervous breakdown; David is her psychiatrist turned lover. After David buys an old Charleston mansion and Kate and her son move in with him, strange events occur including the discoveries of a secret hidden attic and the diary of the murderous slave trader who owned the home. Kate hears a piano playing by itself and sees the ghost of the slave trader who once lived there. Their relationship is strained by the bizarre events as Kate's sanity is again questioned as she insists what she's seen is real...but is it?