fuck his girl friend

While it's true that Mormons are not one-dimensional and completely predictable, the odds of fayetality successful relationship, given the OP's description of his girlfriend, are slim. I have known many women who have married non-members fayetality are happy. She will be surprised that a non-Mormon holds the same values she does and respect you. You should certainly still date even if you are not looking for a marriage partner.