THANK YOU SO MUCH FOR THIS (both parts).
However, the bit about my ex is what I most needed to hear.
I've found, online, at least, since I have few people to tell in person, there are three gut reactions to my story:
1. If anyone did that to my kid, I'd kill them.
Easier said than done and following through with that has boatloads of consequences.
2. Get these kids away from their mom.
Not always that easy or straightforward; in my situation, it's been suggested removing them could cause more harm. It's not their mom that was the problem, it was him; however, their mom did react poorly. Also, it's not just as easy as asking; even CPS agreed, after speaking with our therapist, her home was safe and it was necessary for our youngest to remain there.
... which leads to 3. HOW CAN A MOTHER SIDE WITH HIM, STAY WITH HIM, VICTIM BLAME, ETC?
While devastating in a different light, her world turned upside down the night she found out. At the same moment, the worst part of the nightmare my daughter was living was now over, minus the therapy she may eventually need. I've had a need to understand my ex's behavior, but couldn't find much online about it (other than learn it's not uncommon). I found this but worried it would be way over my head.