1st, my heart goes out to you.
2nd, this link is about a family (not divorced) with a son that had drug issues, and ended up killing his father, beating his mother, and one of his brothers, in front of his 8 year old sister. I don't mean to be melodramatic, but thought maybe if you showed it to your DH he could get some perspective. Regardless if you stay or if you go, him being in you daughters life and being affiliated with his troubled older kids would worry the hell out of me as a bystander, much less as her mother. I hope this in some small way helps. The details about the 8 year old and what she witnessed, and did are very compelling.
3rd I hope things get better for your family soon. It's heartbreaking just to read your posts.
Re: j+k
I had to DD because TMI.
I just wanted to point out that this is a kid that didn't come from divorced family (excuse/reason/etc) for getting into trouble, seemed like a nice "normal" family and still look what happened. The parents were able to put their other kids 1st it seems and remove him from the home. And he is 17 not 30.
j+k's DH seems to me to have guilt about the grown kids, but I thought if he saw this, and that it happens to even "together" families, it would open his eyes a little. Maybe that is naive of me, but one can hope.
I appreciate the gesture and the intent behind your post.
Just so you know, SS is no longer in our home and he is not returning. If/when we divorce, the CO will state that DH will not allow SS and SD to have unsupervised visits when DD is with him. I will not back down from this and I will demand it. I also will not allow DH to remove DD from this state to where his other kids are. Unless DH lives here in the same state, DD will likely not see much of her half siblings. Can I 100% prevent it? No, but I will do all I can to try.