Divorce

I have been married since 1999. My husband is an army officer. We have two daughters. one of them is in senior secondary school and the other is in college. He has been doing domestic violence and emotional abuse from the beginning. he doesn't allow my kids and me to go anywhere and doesn't give us any money. he spends on basic expenditure that too extremely very low which is now decreased. He has an extramarital affair that we know of but we don't have proof of it. from the beginning, he has had many issues with us. He only spends money on his brother and his family. my kids are eyewitnesses of the abuse done by him. we have a voice recording of him admitting to doing domestic violence and he has also kicked me out of the house many times before. Due to him, I was diagnosed with depression for which he didn't pay for the full treatment. I and my kids are financially dependant on him because he does not let me work. He refused to pay for a lot of my treatments due to which my family and friends gave their money and I have bills to prove it My and my kids want to separate from him but we don't have any money to pay for things. we also want our alimony and kid's expenditure for school and college fees. what can we do in such a situation when he used his position and rank to manipulate and dominate us?