cath if you divorce him, you will be entitled to a share of the house, and he will need to make maintenance payments, so you could well be better off financially without him. You will undoubtably be better off emotionally without him.
You are a very strong woman to bear this and still have some sense of who you are! But please, please, start making an exit plan. To continue in this situation is damaging to you and your DC. You probably won't realise how much until you are out of it.
Am I right in thinking that you see your business as a way out on some level? I wonder if he know this too (even if only subconsciously) - he is using money to control you and keep you as his possession. However new businesses are risky (as I'm sure you know) and I reckon it probably makes sense to start making plans sooner than that.
I think you need to know about where you stand. Why not go and see a divorce laywer just to find out how it works and what it's likely you'd be entitled to. (He doesn't need to know, you're not committing to a divorce, just getting information!)
And if you think in your heart of hearts that divorce is on the cards eventually (and it should be IMO, you're being abused) I'd advise you to seriously think about getting on with it: legal aid for divorce is disappearing in April IIRC. If you divorce him now, you'll may well get a much better deal for you and your DCs.
Maybe put off relying on the business to get you out just for now? He's going to make it as hard as he can. And instead work on getting your independence from this abusive man, as a precursor to setting up your business and starting a new life.
I was in an abusive relationship before. I am now with a wonderful man who is my best friend and would go out of his way to do anything for me and the DCs. (DP used to be a chef and does all the cooking for example. We share stuff like bedtime, baths and cleaning, even in periods when he's working and I'm not). You deserve to be well treated, you really don't deserve the existence you're enduring right now, nor do your DCs. But only you can do something about it. Your H won't change, the only way to get change is to get away from him.