Mother Love (1989)

A British yuppie couple have a seemingly idyllic existence. But there is one troubling factor in their lives - the husband's eccentric and sometimes difficult mother. Her odd behavior manifests itself in a series of incidents involving her ex-husband, a concert musician, and her ex-husband's new wife, an artist. Flashbacks reveal bits of her troubled past. Little by little, the young couple's life begins to fall apart as the mother begins to act out her feelings of intense jealousy in the form of revenge, implicating a dear old friend, and leading to murder.