How Does It Work In Your Head?

I have been thinking about a few of my exes recently ones from many years ago and some more recent and I don't understand how it works in their heads very well. I don't see how people can decide to ruin a persons life and see themselves as the good guy How do could they do some of the things they did and still think they are the innocent ones and I don't mean my exes who couldn't communicate well but the ones who abused and hurt just about everyone around them and then turned around and played the victim it does not make sense to me at all I also don't understand how people like me are accused of the same thing because a doctor slapped a certain label on me I guess I just don't understand how people go around refusing to acknowledge the hurt they have done to others but i dont know maybe they think the same about me