If she says she misses you but wants nothing to do with you, she’s either using you or something is conflicting that is preventing her from doing so. Find out what’s happening. If you really think she’s the one, lay it all out on the line, tell her how you feel and that you can work through whatever is going on. If she still doesn’t want you, then it’s not meant to be. Sometimes you just have to cut you losses and move on with time.