At some point, you get hurt enough it doesn't matter any more. Unfortunately it isn't just physical that hurts.I've just now related it to when my mom's boyfriend just finished beating the shit out of me. I was about 6 at the time, I had the bright idea of quoting a movie line, "Is that all you got?!"
There is no "lets find how you can join in" in the schoolyard there's just getting picked last and picked on because it's easy and everyone thinks your exaggerated startle response is funny.
Doesn't matter though, it gives you that attitude that you are damn well going to do it and you are tough enough to handle the results. Except PTSD attacks in the one place we can't we can't defend.