So the first thing I suggest you do is to get a bank account with a totally different bank to any that he uses or knows about. Then whatever money you are able to put in a bit at a time starts your independence. Then if you have a passport take it and any other documents you have and either leave them with a trusted friend, after taking copies of them too, or get a deposit box in a bank so that they are safe and cannot be taken from you. Vindictive people like your husband are quite likely to try and destroy or take things just to keep you stuck with him. When you are on your own start a methodical sift through all documents such as pay slips, and take photos of them, because in the future you may be sure he will try and lie his way about them. Just try to behave as you are normally doing at the moment while you collect all this evidence. Start looking at a variety of things, such as could you afford a flat or a bedsit on your own, where is there a womans refuge, and make sure you have the phone number and information about that , but make it in some form of code so that it will not be visible to him. Collect together all precious photos especially of early pictures of your children and also any you have from your own childhood and your parents. He is quite likely to try and destroy them to upset you. Listen to views from people you trust as to who has a good name as a solictor etc, check up on the phone numbers of the local police, just in case you need them. Carry on thinking about all aspects of your life and look around at friends and see how they are living and decide where you want to end up, and that will help you to find a way to go to the place you want.
As far as we know we only have one life. You have coped with a lot of rotten times in your life and you deserve some happiness that is not backed by fear and worry . I would also write down a couple of the awful situations you have faced and fold them up and put them in an envelope and seal it up and put it somewhere safe. That is so that if you leave him and he then comes round saying he will change and life will be different. dont believe him at all. He only wants to get you to go back to him so that he can either then leave you, or make the rest of your life miserable. Open the envelope and remind yourself of the reality that cannot be ignored and dont let him wheedle his way back to you.
There is little you can do about the past, but you can be in charge of your own future and enjoy what life you have in front of you. The bliss of doing things your way without having to defend it, or alter it just for this bully to carry on in his appalling way. Write up a weeks diary (carefully hidden or kept somewhere at work not at home) and dont exsagerate but just simply write the truth as it happens. Then when you are ready, leave in the way you want, tell your children , they may already know just what he is like, but if not you can give them that to read and to see just a taste of what your life has been like. It will be brilliant , that family and friends now know exactly what he is like and can despise him as we do. He will not like his cover blown and people knowing just what he is like. He will bluster and lie and you dont need to say anything extra, just tell the truth and when he comes up with some plausable rubbish simply state that that is not the truth and say things like. " Dont you remember telling me to go to bed straight away " etc. You dont need to remember things to keep up with lies , just tell the way things are.
Every day you have without him is a better day in your life, and your life may consist of little money but such a relief and calmness and if you have that in life you will also live longer. His behaviour is such that you cannot be sure that he will not descend to physical abuse too, and also you might end up with a heart attack or stroke from coping with this disgusting behaviour. Start today, and as you gather all your thoughts and ideas about what you want to do and work out how to do it, you will be pleased to be back in charge of your life. Every good luck to you and let us know how you get on. We will all be thinking of you and hoping that you find the strength to get out of this awful situation.