You need confidence
From what you said, I can sense your husband has some mental problem, your son can see it, you just ignored it, did you try send him to see a doctor? He has typical controlling charactor, you might need some profesional help.
If only reason you stay in the marriage is children, did you ask yourself this family will give childrean happiness or sadness? Can they grow up without copy their dad. Most likely children will repeat the pattern, you need to think about break the cycle.
If you trust your instinct, do your research, help yourself, you are lucky if he want to divorce. He need pay high price. Even you stay, let him know you are confident, he knows your weekness(not exactly, sometime too kind is weekness too) and use it against you.
Never try to find someone save you, you are a very nice woman, deserve be treated better, but only if you be mentally independent, only after you are free, otherwise you might fall in same trap. Respect came from trust.