There are a couple similar stories. The one I'm looking for, I remember it being a multipart story. There is an eighteen year old girl living across the street from a woman that doesn't like her or trust her. To get revenge the girl comes onto the husband. He is a stay at home writer. They work it out that he will hire her as an intern and housekeeper. They even discuss it with her dad at a neighborhood party that he's hosting. The wife still doesn't trust her and gives her crappy jobs to do around the house. Of course, she does not work in the home, so she's not around to see her husband and the neighbor having sex.