Complicated Ex-Girlfriend Situation?

Aw that is cute you really care about her and want her back but if she is not feeling it then i would leave it alone longer. If you don't want to do that then you could be more direct with things. For example call her and say "We are going to --insert activity-- tonight/today/in thirty minutes, ill come pick you up, be ready." Then hang the phone up. Don't let her have a chance to tell you another time or that she can't. Also never leave the hanging out to her, she will keep putting it off. But keep being supportive though, i am sure she really appreciates it.