Look here buddy. I don't want to sound like I'm scolding you but if she doesn't want to date you it doesn't really mean you lack something. It's her choice to date or not to date whoever she pleases and you have to learn to cope with that. Like some character (I don't remember the name) from Game of Thrones said: A man comes to a woman and tells her he loves her. The woman rejects him and the man leaves. Who lost something?. Most people would say the man. But no, the man lost a woman who didn't love him but the woman lost a man that loved her. See what I'm trying to say? You might not have a relationship with this girl but another will come. Don't lose hope. Remember, relationships work best if you don't really need one to be happy if that makes any sense.