NC but struggling

NC but struggling with constant harassment

I have been NC with my Nmother for exactly one year. In this year, she has slandered me to anyone who will listen, accused family members of encouraging the cut off and even prompting it, and has been trying every possible way to get in contact indirectly. Thankfully we live in another state but her attacks and reactions are escalating. My brother told me that she wants to file a lawsuit against me and my aunt told me that if anything happens it will be my fault. I am keeping my boundaries firm but this seems never ending. My mother is obviously not mentally well but no one will do anything about it beyond tell me that she’s my mom and I can’t do this to her.

Has anyone experienced something similar and if so did ever stop?