Don't know what to do with girlfriend?

Well, talk to her. She's half of this relationship, so she deserves to know what you having been thinking. At the very least, ask her what she thinks she wants out of the relationship, because I know you said she doesn't know. It's natural to want to explore other relationships. And it might be her way of saying that she wants to explore others without hurting you. If you two are meant to be, you'll be in the end.