Why do I only have bad guy friends?

I think you may be attracted to bad boys because they reinforce you negative self image. They feed on it actually. They confirm what you believe by being less than considerate and you feel comradery because they are telling you that they will be complicit in your low self esteem. They are your partners in crime, so to speak. There is nothing wrong with you. You simply need to how the way you think affects the way you behave.