My ex girlfriend randomly wanted to be just friends after we started talking again?

Ok so my ex gf of 3 years and me just recently began talking again. she had dated a few guys between our last breakup and now, but she never seemed to have any luck with them. she is a virgin , but after we had not seen each other throughout our first year of college, she approached me wanting me to take her virginity during this summer. I always wanted her to keep that for the person she was going to marry, but I am far from a virgin. She seemed fine with going on dates again, but when we went on a trip a few weeks ago she told me right before that she just wants to do the right thing and still be friends. This similar situation has happened 3 times already before. She told me the reason why she wants to be friends is that I try to act like something I'm not (A more mature person, a gentleman, always paying for everything, and sometimes like to be sexual) these are all thing that I always have done and enjoyed doing, but have never been extreme with the sexual part. It just makes me feel that she uses me for going on dates and vacations so that she will not be bored. For example, last year I was going to Alaska for a business trip and I took her along, she didn't have much to do with me after and her excuse was we were about to be going to different colleges. She has been messing with my head for too long and I don't know what to do. I love the girl to death because we have practically been off and on since first grade, and I just don't know what to do. I just feel like she lets her friends and sister influence her decisions and she doesn't let her heart speak for itself. She means the absolute world to me and I only want her happiness whether this means her ending up with me or not. what do you think?