Piggy in the middle between dh and dd

[Hufflepuff7]

I'm finding it really hard at the moment feeling like piggy in the middle between dh and dd20. They have argued and made up for years but about a month ago they had a huge argument that resulted in pushing and shoving on both sides. Dd20 now accuses dh of abusing her even though she tried to throw a punch at him first. He defended himself by stopping her and pushing her away. She's told me I should leave him because of this and told me I'm a bad mother. She's said once she moves out she wants nothing to do with me but yet speaks to me like nothing has happened at other times.

I've been in tears and lost weight over it all. I've always been there for her and she knows it really so what she's saying hurts. She even resents me speaking to him on the phone when she's around (he works away) saying that it 'triggers' her.

She's moving out again to go back to uni but I am feeling like I'm responsible for finding a place to live and sorting everything for her. She's said to me that he should be moving out not her.

Dh is always asking when she's moving out and I feel pressure then from him because I'm trying to find her somewhere to live but it's not easy when her uni is miles away.

Dd17 says that dd20 is manipulating me and using emotional blackmail and she's probably right. Dd20 has been very spiteful for a while now and everyone seems to be 'getting it'.

I just don't know how to deal with all the animosity between them and even find myself worrying about Christmas!

@user27424799642256 I have NEVER told her I don't believe her. I have kept those thoughts to myself. I have asked her if she would like to take things further and get help for what happened multiple times. She has said she doesn't want to take it further but is in counselling. I have asked her if she wants to talk about it multiple times, she said no. I of course respect her decision. I have not demonised her at all.

@Cocomarine thank you for sharing your experience too. I am very aware that they feel differently about things and remember things very differently. I don't think dd20 is wrong for feeling like she does but it's her attitude in being so nasty to everyone, not just the family, and that she is so ungrateful that I have a problem with.
You're right, I didn't really have much of a choice in leaving but at the same time I felt I should be there to help him too. I tried to be there for everyone and apparently failed.
I feel guilty all the time about choices I've made but then wonder if making different ones would have caused different issues.

@Ponoka7 I tried to get dd20 help as a younger teen but she refused to go. I'm very glad she's getting help now but obviously there's a lot more going on.