Just break off contact. Don’t call her, do not answer or return her calls/e-mails. Just put a lot of distance between the two of you. I don’t think it would pay to tell her how she has hurt you. She’ll probably try to come up with a better story on how you have wronged her in some way! She’ll either get the hint or she’ll be so self absorbed she won’t even notice that you have excused yourself from her life.

With friends like this, who needs enemy? Just walk away. If she calls you and ask you why, don’t need to worry that she will be hurt. Just tell her whatever you are feeling. If she realise her mistakes, she will know what to do. If not, you don’t lose anything by losing her.