Kirsty, try not to beat yourself up. I too, after a couple of drinks let rip once. I really gave it both barrels and called him and the OW everything.
I woke the next day thinking I’d blown it and undone all the good work I’d done DBing. It didn’t. He actually expected worse.
I just told myself I’m only human and I’m hurt and angry. It had to come out sometime.
Learn from it, you got it off your chest but leave it now and make sure you don’t drink in his company again. You don’t want him thinking that every time you have a few he’s going to be called names again.
That is what my H was worried about if he came back. He’s been back a year now and I’ve slipped up once in that time.
But I know that he cannot change the past and I have to let it go for the sake of our new relationship.