I get it. I really do.
For me, the thing is to stop my own raging when she riles me up.
I must let it flow out, like bad energy, so that I can enjoy something about this day in my life.
So I have to work on not dwelling on it.
Let all the rage out, scream, or write to a fictitious email address, or whatever way you want to that isn't engaging with her...
Then --the important part--how can you stop dwelling to enjoy some part of your day? What can you do to take your mind off this?
That's important to stop hurting yourself by letting this ruin your day.
She does sound borderline indeed. The family dynamics sound familiar!
Mother topics on here get me very riled up.
So I have to go save my day --other thoughts, other actions, happy thoughts or actions, or even just distractions...
save yours!