That could have been me who wrote your post. I understand the being frozen and feeling powerless to do anything, what many don't realise is that the time you leave is dangerous, men often become more abusive because they perceive that their control over you is threatened. Before you leave you need to put everything on place, remove treasured belongings and important documents, and gather info on his finances so when you do go for divorce he can't hide it. There is also the worry when you get older about pensions, starting again. I would back up the suggestion to read lundy Bancroft and look up the freedom programme, now you can do it online, the facilitators stress that you shouldn't leave without making all the necessary preparations (unless obviously your life is in danger) and no one will tell you to leave, and also suggest that you don't change your behaviour to him as you learn more, as he will suspect something. Your children will know what their father is like and will not blame you for leaving. See a solicitor in confidence to find out what the outcome is likely to be. One thing to do is make your will so anything goes to your children, eventually you will need to sever your joint tenancy of the house if as was common back then the house is in joint ownership, he will be told so take advice on when best to do this.
An abused person should not have joint counselling with their abuser, so no more of that, go for counselling for yourself, maybe your doc could refer you
In my case he ended up leaving me for someone else, and looking back I'm so much better without him, I have more than half his pension, a house and the support of my children, it's me they see mist not him. In a normal year I'd be staying with my son, nor sure what will be happening cis of covid. I discovered more stuff about him that I'd not known and even had he been sweetness and light I should have left him
Hope eventually you end up happy, even though you might have difficult times to get there