Personally, I think that if you truly loved her, you would be able to be there for her and support her, even if it's from the sidelines. But that's just the romantic in me.
The answer to your question is this: It's better to talk things out rather than to just dump her and never speak to her again. That would just be immature. You need to tell her what you're feeling everything she calls you "as a friend" and tell her that you can't just be there whenever it suits her. If she's just using you like some kind of therapist, then, what the heck. She's being completely selfish and has a complete disregard for your feelings.
Seriously, talk things out. Don't a kid about it. You need to find some kind of courage to get past this fear of losing her. Love is one big gamble. You're not going to get anywhere if you don't take a chance at something. If you lose her, you lose her. If you get her, you get her.
Hope that helps! Good luck.
SAULE. reaching for something higher than the sky.