Punch the bitch in the face to relieve stress. From the sounds of things, it'd help you more than a stress ball.

My SIL is just like that. She's a perverse narcissist. She blew up when she found that my brother/her husband was writing to me from a private email she knew nothing about. She complained to my father who then told me she was worried that we were saying nasty things about her behind her back. I had to spell it out to him that 1. My brother and I were allowed to discuss stuff in private with each other 2. I hadn't seen her in years at that point so I'm not sure what I'd have to tell him about, so either she has a fertile imagination or she knows damn well that I had jolly good reasons for not wanting to see her any more, reasons that were worth bearing a grudge over for more than a decade. I'd suggest you break off all contact with your mother and then just have therapy to be able to embrace the world afresh, there's absolutely no point even trying to deal with that level of narcissic personality disorder. There is no cure that we're aware of, believe me I've searched for one.