I've decided the one thing I can definitely do is to make sure that I am always using kind and positive language. I will never resort to sweating and abuse. It says more about the person using the language than the person it is aimed at.
It is very, very usual in an abusive relationship for the abused to hang on for dear life to the small illusion that they are a better person for being able to be 'nice'. It is SO common that almost all abused women will recognise this in some way in themselves. It is a trap because it makes you have something to feel good about yourself in a relationship where you and your feelings are otherwise almost completely unacknowleged and never validated. It is the beginning of a toxic co-dependancy.
Honestly why am I not leaving him.... because last week I found a piece of paper with notes about various 2 bed flats in our area. He is clearly thinking of leaving.
From everything you have said about him, he is classic, textbook passive-aggresive. He left this for you to find. You do not have to be passive in waiting for him leave. You can leave because YOU want to.
I know it's awful. But somehow if I try to leave, he will have the upper hand. If I leave he will tell my daughter that everything is falling apart because of me and blame me. It's not just the language it's the way he blames me for everything.
Why are you so frightened by what you think he will tell your daughter about you if you leave? Can you actually look at that 'in the face' so to speak, and see exactly why this worries you? Is this 'upper hand' that so worries you a real thing in the real world of people getting on with their lives? Or just an unreal ghoulie in your fears?
Do you think you give your daughter the right tools to deal with life if every time someone calls her or her mum an idiot (and worse) that you need to be kind and positive about it? Is this why you fear that she cannot tell right from wrong and will believe her father?
This fear that she will somehow believe him is because you are so unclear about your own boundaries. You are pushing back at your husband on his terms. You will never win. You need to find what YOU need.
Stop living in his life. Find your own.