Justin Bieber and Selena Gomez broke up

Justin Bieber and Selena Gomez broke up because she "strayed," reveals Star. The mag notes that Bieber even alluded to her cheating at a recent concert by performing Justin Timberlake's song, "Cry Me a River," which was written "about Britney Spears after she allegedly cheated on him." For whom Gomez cheated with, and how Bieber found out, go to Gossip Cop.