Kristen Stewart and Robert Pattinson’s fairytale romance was damaged when pictures of her cheating with director Rupert Sanders emerged. (6/28)

Kristen kissed Rupert Sanders on camera and that made some controversy because she was already in a relationship with Pattinson at that time.

Arnold Schwarzenegger famously fathered a son with his family’s housekeeper during his marriage to Maria Shriver. (5/28)

Hugh Grant cheated on Elizabeth Hurley with a sex worker. (7/28)