I've terminated a toxic friendship and now she's trying to ruin my life
What did you do to her to make her so mad that she would try to ruin your life?
I never apologized for what I did
It can be hard to get away from someone that is trying to seek vengeance against you, but sticking around while this woman meddles in your life isn't prudent. Get away from her any way that you can and start your life over again.
No, I want to deal with this and not be forced to make a new life.
If you know what the problem is you should try to go and apologize ASAP. If she can't accept it, you may just have to learn to live with it.