For a man, realizing that his partner may not be the right one is probably one of the hardest things to accept. I mean we've spent time, money and a lot of energy to woe her, so if we find out that our relationship is not working out, it's difficult.
Let me tell you, being a dumper is not easy. It's not only the girl you'll upset by the action, there's also her friends. People will call you cruel, cold-blooded, remorseless, stupid, ugly, and fat. You'll always be the villain, no matter what your reason is. So no, it's not fun at all.