Mother-in-law Hell

I met my boyfriend (will be husband one day) at work 2 years ago. Unfortunately, his mother also worked there and was also my boss. I debated heavily about dating him in the first place because I didn’t want to jeopardize my job but got along well with his mother and decided I wanted to be with him….afterall, you can’t control who you fall in love with.
Throughout the 2 years of knowing her outside of work, I began to see her true colors. She was very unstable as far as her mood, she would throw tantrums and treat her sons and husband like they were dirt for no reason.. Throw things at them, threaten them..over react about things such as “how inappropriate it is that my boyfriend stand in the same room with me if she wasnt in there”….the list goes on. Unfortunately, the males in the family are very submissive so no one will stand up to her and the behavior continues. Their philosophy is “just ignore it and it will go away”
Even though I didnt agree with the way she treated her family I never really had any personal encounters.. although with every incident, my patience grew weaker.
Over the past 2-3 months at work, there have been a lot of changes in our company. A new director was hired and was not happy with how management was currently running….and the rumblings of layoffs began. Shortly after, my future MIL/boss started to treat me very poorly..talking to me like I was stupid, being very rude to me in front of everyone and being in my opinion unprofessional. On a strictly business level(not personal), I filed a complaint to her boss 2 weeks ago.
Fast forward to today. Today human resources came in and fired every single manager we had. (Again, this was expected a long time ago.)
She called my boyfriend in a fit of rage telling him how Im a bad person and a back stabber and asking him “do you really want to be with someone like that for the rest of your life?”. Long story short she is blaming me for her being fired!
If ONLY I had the power to fire people… Im a low man on the totum pole and dont feel that my complaint had anything to do with it. She was going to be let go either way. I didn’t complain about any of the other managers and they were let go too.. so obviously it has nothing to do with me.
She now hates me and has told my boyfriend she doesnt want him to see me anymore and how Im banned from the family,etc.
Its already causing a rift between me and my boyfriend because Im putting the pressure on him to stand up to her. I want him to say, “my girlfriend is a part of my life and shes not going anywhere, she did not get you fired and you WILL not treat her any differently or you will lose me.”
I would say that to my mother if this was the other way around. But I know that won’t happen and Im just anticpating the crap thats going to go down. I hope she begins to think rationally about this and realizes that I had no power to get her fired.
Just a word of advice to everyone. NEVER DATE YOUR BOSS’S SON!!!!