How to Make a Bed (1981)

George, an aging elderly gentleman, finds himself in the middle of a mid-life crisis. An affair with a younger woman makes him blossom. However, his wife soon finds out what her husband is up to without her and takes this as license to have an affair with a younger man. Turbulent complications are the result, because everyone tries to keep everything a secret from the other. That can only go haywire.