I don't usually read dating articles (married to a great woman now), but this one hit a nerve with me because I was exactly like you. I was a nerdy, medium attractive tall, slim guy but was too shy or whatever to go on a lot of dates. I would go years without a date. I even had very attractive women hit on me, but I was like "why is she talking to me?" and then sabotage it in some way. I think I eventually grew out of it when I hit 30 and started dating more because I stopped getting so wrapped up in it and just being myself.