How to deal with an ex-friend that I dumped because she was insidious, mean and envious.?

This is a life long chilhood friend that I later always kept at bay because she was always a caddy envious friend that always found an insidious way to undermine your self-esteem (you know the type.) They give back handed compliments, find something wrong with your outfit when you look great, etc. We had it out - I called her out on her behavior, now I just want to keep her the hell away from, but she finds ways to cause me unnecessary annoyance and trouble, such as threatening my business. How does one drive such a person 1000 miles away?