Short story in the collection Athletic Shorts by Chris Crutcher. Our hero is a high-school student; his parents divorced and both are now in lesbian and gay couples. This is prominent background rather than the foreground of the story; the story is centered on Angus, and his parents' orientation is one of several things he's teased about at school. He is on good terms with both his parents.
YA: A Brief Moment in the Life of Angus Bethune