It's not always a snuggle bunny a man wants. Some of them had snuggle bunnies at home, some of them have wives more beautiful than they could ever find again, some of them have wives who are perfect friends. It's just not enough. I've known a few who've left their wives as well, all of them for a younger woman. In my opinion, they left their wives because they fear death. If you notice, the older the man is, the younger the woman he seeks.
The best way to frustrate a cyberbully is to ignore him.