If you feel that something's not quite right when it comes to your relationship, don't instantly blame it on yourself. If your boyfriend's behavior is intolerable, then it's time to think a bit more about his actions. It takes two serious and mature people to build a stable and quality relationship. One cannot simply do it on your own. Of course, no one is perfect, but there are some bad qualities in a man that you should definitely be aware of. Here are the 12 most common traits of a bad boyfriend.