Breaking up is hard to do. You know it, your parents know it — Neil Sedaka even wrote a song about it. Since people have been falling in love and breaking each other's hearts for centuries, you'd think we'd have figured out a way to make the whole thing easier. After all, we've been to the moon.Unfortunately, advanced technology will likely never be capable of mending a broken heart — so. The below reasons why people break up are based on two public studies. One is from the Journal Of Social Psychology, and the other is from the Journal of Adolescent Research. (1) (2) 1. Infidelity. Cheaters have a significant flaw embedded in their minds. They value self-gratification over intimacy and honesty.