I'm so happy that you've found someone who gets all the issues and will support you with the sheriff. I hope that the DC are able to share honestly with her too.
As for shielding them, sadly it has gone beyond that. If he had been a better man/ father it would never have come to this. HE caused it, never forget that.
I had my DD at CAMHS the other day, she is 14 now, and for the first time I heard her speak about our whole sorry saga. I tried so hard to protect her from it, to keep it to myself, but out it all came ....coercion, lying, gaslighting, intimidation, financial control, bullying, rages, narcissistic behaviour, blaming me, selfishness, abandonment of the DC... everything. And she told him she thought I had PTSD and still lived in fear of him. I was so sad she had to live through all that, gutted that I couldn't protect her from it... but the counsellor said that it was clear I had done everything I could and tried to make up for him for years, tried to make their life better, but at the end of the day he was the one who needed to change, not me, and I had to let that go now.
I think you are in the same place with it all Onit.
On a more positive note, I'm off to find that weight loss thread. Not only am I letting go my attempts to make up for my DC having a crap father, I'm letting go the extra weight I have piled on as a "coping" strategy.