Secrets of a Willing Wife (1979)

Upon returning home from a day of shopping, Susana, our New York housewife is startled to find her husband Martin cavorting in bed with Jeannie, her best friend. She throws down her wedding band and storms out. The distressed wife concludes that only her own sexual inadequacy would cause her husband to have another woman in her bed and on the advice of her psychiatrist, she visits CheeChee, a sex therapist with racy ideas about how to cure marital problems. CheeChee sends our "willing wife" on a series of sensual, hilarious escapades. She learns about herself, eliminates her inhibitions, gains confidence in her amatory skills, and soon is ready to win her husband back.