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Ok, I think I have a good understanding of the subject. Well, if you promised yourself that you would trust her, you should try to stick to that. It is natural that you might feel upset that she is hanging with her ex, but at this point she is communicating to you regularly and divulging everything, so she trusts you. Since you actually aren't boyfriend/girlfriend, but would like that to develop, I would continue to be her trusted friend who she confides in. This is the best way to develop a romantic relationship as it creates a great foundation through the friendship. I wouldn't say anything at this point, because you don't have an exclusive relationship with her and she may feel you are being too demanding. Friends don't tell friends who to hang out with. Just continue to earn her trust, and if she tells you she is getting re-involved with her ex, then you can decide if you want to talk to her about your feelings and having a romantic relationship with her. Since you are two hours apart, this may be something to think about and consider if a romantic relationship would even work. That is a personal decision- it works for some and not for others. So, in summary, it is natural to have these feelings, but discuss them with a friend, not her, for now. See what develops and go from there. I hope this helps. If you feel I have answered adequately, please rate my service as positive. If not, let me know what else you need. Thank you for the opportunity to be of service.