It is difficult for you to satisfy them, because their ideas are feudal, or utilitarian and selfish. This manual workshop-style way of thinking does not spare even sons, let alone daughters-in-law.
If you continue to work in this place, it will only make your mental state more tense and even question your life, and they will not agree with you because of it. Of course, if you go out to work, they will treat you cruelly and even sow discord between you and your husband.
You have children. You can't just leave them. Besides, aren't you going to marry him alive? If you give up directly for the sake of unsatisfactory environment and don't work hard, won't all your previous vows and forbearance become jokes?
I don't know if your husband has any friends, you can encourage him to go out to some classmates' parties more often, so that he may have some ideas when he sees that he is financially dependent. At the meeting, at least he still had an ideal, and on this basis, he sought his support.
In short, your husband's family is unreliable, and you live by their industry, so the older you get, the more trouble you have.