I have potty trained two kids and been with many friends as they have gone through the process as well... my best advice is to just let it go... she will potty train eventually... you don't see many teenagers in diapers!

There are a few key things that need to be in place for her to be successful.

1.) She needs to be in control of her functions enough that she knows before she goes!  
2.) She needs to want to do it at some level... my son could control himself but never wanted to sit on the potty... I bought him a "potty present" he chose a harmonica, that sat on a shelf high up and he only got to play with it when he sat on the potty.  I did not put any pressure on him to go or not go, just to sit.  
3.) Avoid the battle of wills at all costs!  If she is resisting you, she will win!  One of my good friends pushed her daughter a little and she ended up refusing to go at all... she had to do all sorts of laxative things and it took months to regulate her system again.  The doctor told my friend to put away the potty and not bring it back out for three months!

Let me know where you think she is on the above... I have a bunch of other tricks and tips I can share to break resistance and increase success!

Shawna