Broken relationship between DD and DH

[2littleterrors]

I don't know what to do. My 18year old DD and DF are at loggerheads with each other.
My DH will not engage with her as he feels she talks to him very disrespectfully.
She can be disrespectful with me also but I do not give her the silent treatment.
We do pull her up when she's being disrespectful but my husband will then carry on giving her the silent treatment.
My DD thinks her DF is rude to her and he just irritates her. She then gives him the silent treatment too.
Truth is they are both very similar, both very stubborn, neither will take the first step towards reconciliation.
I am caught in the middle as they will both then look to me to talk to the other.
It's very stressful for both myself and DS.
She's at home from uni and the last 2 weeks have been stressful. I just want some peace in the house and it seems the only time we get this is when DD is away at Uni.
It breaks my heart to see their relationship being torn apart through sheer stubbornness.
What do I do?

It sounds to me like your dh needs to grow up.
Yes, technically at 18, they are adults, but in their relationship he needs to be the adult. He will just drive her further away and she won't want to come home for the holidays.

Yes that's exactly what I have been telling him.
All he wants is a bit if respect, but she only gives him that when she wants something.
She was the same with me, but I do pull her up in it and then move on.
It's really upsetting me that they can't seem to get on. I don't want her driven away.
I have asked them both to sit down with me present to try and sort things out, but neither want to do that.
I'm at a loss as to what to do. The stress of it all is making me I'll.

Giving no someone the silent treatment longer than the initial incident isn't parenting. You model the behaviour you want. Wanting respect isn't the same as having a household where respect is given and received and expected.

I think there's a teenage version of How to talk so kids will listen. Get him to read it!

This is what I have been trying to tell him. It seems to be falling on deaf ears.
I have told him he is the adult and he needs to lead by example.
I just want him to have a better relationship with his daughter.
I'm frightened that the older she is getting the harder it will be for him to reconcile with her.
She has told me she has lost interest but I don't believe it. I think she is just saying that but deep down she's hurting.

Unfortunately you can't make him.

You can only change the things you do. In my case I told DH and DD (5 yo at the time!) that I would no longer referee so they would have to work things out. They were better when they both couldn't appeal to me.