How long you been split up. My advise would be to go NC for a while, let the 'dust' settle, learn from what went wrong, grow as a person and most importantly learn to be happy alone. If you can do that then your ahead of the 'game'!
You yourself probably know if she or more like you is affecting you more than a person should. Sometimes we just have to make a clean break to get ourself back for our own emotional and physical well being, I had to! Although she still is in my thoughts a lot of the day its better than being confused all the time in contact with someone you still care deeply about.
You will probably find out you are simply a 'friend' and your be gutted! Learn the hard way if you want. I did.