You haven't demonstrated higher value. She thinks your attractive but you haven't showered her why you're special. You haven't proven what makes you different than the other guy?
I was in a similar situation with the first girl I dated after a long term relationship. You can quit and walk away, which was my first instinct, but no woman is attracted to a quitter. Women are attracted to men who are cunning.
The next time I spoke to her I talked about some more unique stories. Living in the Middle east, living in South America, my business, the art collection I dream of (I hate art) etc but not in a braggy douchy sort of way. Then I explained why I could never date her. I think I told her that my family would be all over her to become more cultured or something and she was like, "what? 'm cultured." I explained why she's not, we had some fun banter and three days later she forgot the other guys name.
Hope that help man...