Hi iwtb,
Your post resonated with me on a lot of levels.
Mostly I want to say this: You're having a low period. A trough. You will have those as you struggle through this very difficult phase. It starts with being triggered, the crazy crap from childhood and a current, chaotic living situation feed it. People being more direct than you would like causes you to hurt and feel defensive and angry. the shame of being educated, a good mother, working with DV victims and still "letting it happen" to you hurts like crazy. (I am exactly like you in that regard.), you lose your job (really??? NOW?!?!?!)
In other words, the powers of the universe are conspiring to kick you when you're down.
I have learned (over 2 years of extricating myself) that it just happens like that sometimes, and the solution lies with you. You breathe, you take a break, you go running, you read a silly novel, you pray or meditate or have quiet time, you stop talking to people who hurt you. You just don't engage with your mother, your AH, those on this board who trigger you (use the ignore button). Stop arguing.
You stop fighting and engaging. You think about the fact that in an exhausted economy, you have been offered a job that gets you and your children AWAY from all this. You breathe deeply that you have been issued a subpoena and surrender to the power of the State.
In fact, surrender to the crap. Stop fighting. Figure out what you can do to make your life more PEACEFUL from today forward. (hint: arguing, fighting back, convincing, persuading aren't compatible with peace).
And you decide what you can do in the next hour to further your serenity. And then the hour after that.
And pretty soon, you will be surprised that you are out of the trough and on your way to a peak.
You have to expect the troughs. Just don't wallow in them. Know that the less energy you give to despair and anger, the sooner the bad phase will pass.
I promise that this is what works for me. I hope it will help you.