Stanley & Iris(1990)

Short pooper:
Stanley (Robert De Niro), having moved to Detroit and improved his life after learning to read and write and getting a better-paying job, returns to ask Iris (Jane Fonda) and her family to come live with him, which she accepts.

Longer version:
When Stanley reveals that he likes to come up with inventions on the side and is currently working on a device that helps cool baked cakes, Iris is impressed. He also tells her that there is a company that has taken interest in his invention and wants to offer him a job, based on it. She encourages him to retake his lessons, which he agrees to. Not too long after, both his level of improvement and confidence grow enough that he can already express himself by means of basic sentences; this also helps him and Iris to grow closer again.

Despite her obvious attraction and feelings for Stanley, Iris still resists him because of the memories of her deceased husband. However, more emboldened than before, Stanley refuses to let go of her, this time. They have an encounter where she shows him a letter she previously wrote for him, expressing her feelings for him, but never sent. Stanley reads it flawlessly, which finally moves Iris to open up to him. They go together to a hotel where they spend the night and make love for the first time.

Some time later, Stanley announces that, based on the success of some of his inventions, he has been offered a well-paying job in Detroit and he will move there, which saddens Iris. However, after a few more months, he surprises Iris by returning, driving a fancy car, and telling her that he has bought a house big enough for all of them -himself, Iris and her family, that is- and he wants to marry Iris and have them all in his life. The movie ends with Iris happily accepting and the two of them embracing.