You can still try with her if you feel there is a chance left of being together. The benefit in trying is that if you do have to move on, you will know you did what you could to make it work. If she continues to reject you, then moving on is a viable option. But until you feel you have done all you can, then you may always question your decision to move on. But if you feel you have tried everything and she is still avoiding any contact, then you may have to move on now.