What do you think about me cheating on my ex-girlfriend?
That's a bad thing. Why did you cheat?
She is a bitch. She made me cheat on her!
It's wrong to cheat. She didn't make you do anything, you chose to cheat.
My girlfriend deserved it, she's a fucking bitch.
If you didn't like your ex-girl friend when you were with her than you should have ended the relationship, rather than just cheat on her. This would have allowed both of you to move on and be happy elsewhere. No matter how she acted, cheating is a choice that you made.