Why do people cheat?

There’s an amazing Ted Talk on infidelity that I recently watched that touches on all of this and I recommend it highly. But if you don’t have time to watch the entire video just read the closing from the video:

I look at affairs from a dual perspective: hurt and betrayal on one side, growth and self-discovery on the other — what it did to you, and what it meant for me. And so when a couple comes to me in the aftermath of an affair that has been revealed, I will often tell them this: Today in the West, most of us are going to have two or three relationships or marriages, and some of us are going to do it with the same person. Your first marriage is over. Would you like to create a second one together?