you are thinking the problem is that maybe you're not good looking enough, or that you have low self esteem... but, perhaps it's a problem with rejection?

Rejection feels awful. Everyone has to endure it from time to time. Hopefully after some time you will feel comfortable around this girl again. In the meantime, I think you could think of it all as developing your skill of dealing with rejection without taking rejection too personally, or to heart. It takes discipline to keep thoughts going in a positive direction when we feel bad. It takes practice. Rejection can overwhelm us, but it can be kept in its place, too.

It's not your fault she has a "type." That's her burden/choice. Hold out for someone you are completely compatible with. She seemed great, but then you found out she has a type right now. You can't work with that. You could say: yeah she's pretty and cool, but I can't work with her romantically because she has a "type."