Welcome to SR. You must feel so terrible lonely. Your childhood story is very difficult to read, as you were the victim of extreme narcissists (yes, narcissists, who inflated themselves even more by fostering two disabled children) and you have now found yourself in another prison run by another extreme narcissist.
I'm glad you got those degrees and I'm glad you're saving money to get out of that marriage and I hope you will not give up your vision of a safe life, with safe people, and a peaceful and loving home for your children--one entirely different from the one in which your own childhood was sacrificed to your parents' selfish egos. (That your mother became a therapist makes me shudder. But I'm not surprised. Narcissists love that kind of power).
Get out as soon as you can. If you can, visit a domestic abuse center for some advice on how to do it in a way that increases your chances of safety. With two babies, you will need some people to have your back.
You deserve to be loved, gently and consistently, without fear or dread, and your children deserve the same. They will suffer if you stay in the marriage and I believe you know that. You are intelligent and resourceful. I believe you will find your way out if you believe you actually are worthy of it. That will be your great challenge.
I hope this forum can be a source of support for you. Many here have had to break away from abusive families and brutal partners. You are not alone.