Its not you, its him. Such men do not change and its worth separating over. Its over anyway because of his abuse of you
(and in turn your children who are witness to all this from him too).
How long have you known him?. Did you meet him when you were very young, say late teens, yourself?. Do not get stuck on the sunken costs fallacy here; the damage is already done.
The only acceptable level of abuse in a relationship is NONE.
Abuse like you describe and it is abuse thrives on secrecy. You've written about him on here and that is an important first step out, you deserve all credit for writing about him as you have done. Please start opening up further to others like a trusted, reliable girlfriend or your parents, they may well have their private based suspicions about him. They should support you. Abusers as well can be quite plausible to those in the outside world too but you know what he is really like behind closed doors.
He is merely projecting his own self hatred onto you; he is the one who people do not get along with etc. He is using you as a scapegoat for all his inherent ills, ills that you did not cause. He does not know what love is and his actions towards you are in no way loving ones. His actions are about power and control; he wants absolute over you (and in turn your sons) here.
You've being emotionally abused by him here and your children, particularly your eldest, will pick up on this if they have not already. They will react to this. They cannot and should not be raised within such a toxic and abusive environment because it will harm them too. Would you want your children to be in a relationship where they go onto swear at their spouses because she has asked a perfectly reasonable question, no you would not. Its not good enough for you either.
You are not at all responsible for his happiness or for he as a person; you are only responsible for your own self here. Abusive people say that its always the other person's fault, that the other person (in this case you here) drove him to behave like this. Its utter rubbish, you have done nothing wrong here. The man would have an argument with and in an empty room.
You are married to this person and thus have rights in law; exercise those and see a Solicitor re your legal rights here asap. Knowledge here too is power.
Its not your fault he is like this, you did not cause this to happen and such men do not change. Talking to him is a waste of time and do not ever entertain the idea of any joint counselling sessions with him.
Look at his parents too OP; I would imagine that his own dad behaves the same towards his mother.
Please contact Womens Aid on 0808 2000 247, they can and will help you also here. Keep posting here too and cover your tracks online; you need a safe outlet.