Mature answers only please. What should I do about my "relationship"?

You can't make yourself love someone it just doesn't work that way. It will never last. This girl seems to want to play around still and not be serious if she wants another girl. Break up with this girl and don't give up on finding real love, because real love that reciprocated is the best thing in the world. Don't sell yourself too short either, at least you care enough to ask. Join a singles site go out more you will find someone you really want. Good Luck!!