15 Lessons Movies Can Teach Us About Cheating

Lesson: Affairs often involve lying and denial.

This depressing drama starts with Jack (Mark Ruffalo) and Edith (Naomi Watts) cheating on their spouses, who in turn start cheating on them with each other. Both "couples" weave a web of lies even as everyone starts to have a pretty good idea of what's going on. The compromised morals on everyone's part add to the bleak hopelessness.