Why does my dad always say this?

So we could be watching t.v. and if someone says the word "bastard" he'll say, "like me". I know his dad wasn't around at all when he was younger, but he doesn't have to call himself a bastard. I want him to stop calling himself that. How do I stop him? And what should I tell him? And when he watches Maury, he's like, "please don't let those kids end up like me."