Most Helpful Guy
If a guy has had 40 relationships, and none have lasted more than a week, obviously girls find something wrong with him. He probably tried to use them all for blowjobs or something along those lines. I don't think you should be paranoid that he might toss you aside, but you should be paranoid that you might be setting yourself up with someone bad.
But what do I know? It's not like I have seen this happen a dozen or so times through my high school life.