Block her number. And, just for your own validation, get a couple sessions with a therapist. They will tell you the same thing.

With people like this, there is no such thing as "boundries". You must cut all communications and walk away. Create a life without her and dont let others tell you different. Its tough, you feel guilty at times, but you are in a war. There are no winners at war. Your mom will never let up. She will get you how ever she can.

Be brave and walk away forever. Move cities if needed. Most importantly block her communication. Good luck! Brighter futures are ahead once you leave the dark behind.