Interestingly, no one has yet suggested to look beyond the surface when considering those 'ugly' and 'horrible' men you talk about. And sll those 'atrocities' they do.
Have you ever considered that all these men are a product of their environment and upbringing? Have you ever thought of their misery as children, affects of the dysfunctional families so many of them come from? Have you thought of a relationship that boy who you will become a villain, had with his mother? Was she caring of him? Was she loving? Was she supporting him to be the best he can be. Chances are very high she wasn't. A child is born into this world pure and innocent. His environment, and first of all his parents, carers and siblings shape him the way he will later be. Then school, failure or success and undoubtedly, genetic predisposition.
Now tell me, if you were coming from such a dysfunctional home and environment with genetic predisposition towards violence, smoking, drinking, dependency of any sort (these are all genetically predisposed conditions), where you saw lots of domestic violence, physical and verbal abuse, poor treatment of women, etc will you become a kind, loving, successful and wonderful in all respects man? You wouldn't.
So here's the answer: for a man to override the traumas, abuse and just unkind treatment he's subjected to as a child, and the pull genetic predisposition exerts on him, he must have pretty damn strong character and will. Not all men posses this. To change yourself is the hardest thing of all.
We've all been damped by our bfs once or twice, but a healthy response to damping is different from yours. Maybe you should investigate the reasons for that response and try to change yourself.
Then you will know first hand how easy it is.