Brutal (1980)

Monica Real is arrested for the murder of her husband and his two friends. Only she knows the reason for the crime, but she is in a trauma. Monica's case draws the interest of Clara Valdez, a feminist and journalist who is living with a young executive. In her investigation of the case, Clara talks to Monica's mother, who tells her of Monica's timidity and her rape by the man she eventually married. Clara also meets Cynthia who reveals Monica's "other" personality, which stemmed from her association with the sexually wayward Cynthia. In the end, Clara convinces Cynthia to pay Monica a last visit. The patient finally speaks and tells of the sexual humiliations that drove her to murder.