How do I ban a fan from my Facebook page who has blocked me so I cannot see them to ban?

I am a photographer, and have a page for this. A personal friend of mine is acting very immature and upset about something and decided to block me. Other people can see that she is still a friend on my page. However I feel as if she decided she can treat me so poorly I would rather not have her as a friend, with the ability to post things that do not need to be publicized and have nothing to do with my job. But I cannot ban her because I cannot see her listed because she blocked me.