You shouldn't sleep with your ex.
Melanie has been feeling lonely and frustrated after a string of unsuccessful dates, and after an especially bad one she receives a text from her ex inviting her over.
Melanie wants to respond to her ex's text.
Melanie responds to her ex by saying that things between them did not work for a reason and that she doesn't want to see him.
Melanie texts back and agrees to come over, and she ends up sleeping with her ex.
Melanie is free to continue dating new people, and she soon finds someone with whom she wants to be in a long term relationship.
Melanie and her ex start dating again and Melanie feels stuck in an unsatisfying relationship.