I understand the starting early thing, the first few times I have sex <at an age that should not even be posted on these boards or spoken of> I don't even count. I started counting at age 16, reasoning that at that age I was finally completely conscious of what I was doing and the ramifications of my actions.
In terms of making girlfriends break up with you, I do the same thing but for different reasons. I push girls away, so I don't have to feel guilty about breaking up with them. I don't want to have to be the bad guy; the guy who calls it quits, gives up, and moves on. I prefer that girls break up with me.