Most Helpful Girl
Well I honestly don't think anyone here can tell you that. You know her better than any of us and you know first hand the relationship you had with her.
However, if she has moved on I think it would be best for you to try to move on as well. If that's too difficult at the moment you should at least try to occupy your time with new people, things, and/or hobbies.
If in the event she does come back to you, make sure that you are on the same page before you get back together. I mean, you both broke up for a reason so I think its important to cover those things and communicate the problems so you can avoid them from happening again. Also make sure that you aren't a go-to rebound for her if things didn't work with this boyfriend and she comes crawling back to you because she knows you'll have her.
Basically do what you know and feel to be right but take care of yourself first because that's what she is doing for herself.