My "friend" is a compulsive liar?

I catch her lieing occasionally but now it's gotten out of hand. She visits my state alot, but she lives one state up. She wanted to hang out with me badly and I said that I was busy. She lied about when she was leaving to manipulate me to hang out with her. That's not the half of it. She lies in practically every conversation I have with her and I don't even know the truth anymore. I don't want to throw away our friendship but something drastic must be done. Is there any way to do a wakeup call to a liar?