Weird. I do the exact same thing except I don't break my hair off, I just twirl it and run my fingers over it. The sensation feels good over my finger tips for some reason. I have to keep my hair short because the urge to do it when I am nervous is pretty strong. I'm not the only one! Thank God.
Speaking of which, I really, really, really need another haircut because my hair gets jacked up from messing with it so much. Do forums attract obsessive compulsive people or something?