I used to get threats that they'd go live with Dad (when I knew darn well that wasn't going to happen).
I have two boys (now 16 and 14), but the combination of tweenhood and our divorce/missing dad situation made it a pretty rough go for a while.
For a while there, DS would get angry with me, then angrier that I wouldn't engage and fight with him, then apologetic that he tried to fight, then repeat all over again. It was exhausting and I never knew what to do. But when I say exhausting...that doesn't do justice to how much it incredibly saps you of your emotional energy...
They DID come through it, and we have an amazing relationship.
Try to let it roll off, forgive, understand, and just be around when the quiet comes. She doesn't mean it.
And you probably already knew XAH was saying these things, so don't let that bug you (even though him saying it to her probably really ticks you off). Sometimes when my kids yelled thugs like that, it was because they couldn't contain the crap he was saying and almost needed to get it out...even if it came out horribly.
It does get much, much better!!!