Our Souls at Night

Louis Waters is a widower. One evening he is visited by Addie, a widow who lives next door. She invites him to sometimes sleep over - platonically - talking in bed to combat loneliness. They try it out, and like it. The community finds out, but assume it's a sexual relationship.

Addie's son dumps his child Jamie with her. Louis helps her care for him, and gets him a dog. After Jamie's father picks him up, Louis and Addie go on a trip and have sex. Read more on Wikipedia.