I had a toxic narcissist as a friend for seven years before I figured it out. The only way to deal with it is to go no contact and cut them out of your life entirely. I know that may sound harsh, but really, if she's toxic to you, it is for your own health. You can also ease out by not replying as much, not seeing them and then eventually going to no contact. However you choose, I wish you well. Toxic narcissists never get better.