Are you familiar with Tony Robbins 6 human needs? If not, google it. I would suggest that right now she is not meeting any of your 6 needs other than maybe uncertainty and I think you would agree it is not in a good way.
I am giving you MY opinion. You have a tendency to think things are getting better and then you temp check her only to get rejected.
Again, I think it's possible you can live comfortably in the friend zone for the foreseen future. The question is how much longer can you live in limbo?