Family help, Abusive Awful Stepfather?

First off this will be long, but thank you for hearing me out.

I'm 23, graduating with my Bachelors a week from now. I spent my college years living with my mom,and stepfather to save money by going to college locally. Unfortunately it was also very stressful, my stepfather is a Mexican immigrant with very different viewpoints and his beliefs on how to live life are very different from my mothers and my other relatives.

My mom married him when I was 7. Ever since then I've lived walking on eggshells. He never tried to learn English, because he has hated the language, and the American culture his entire life. That lead for terrible communication between myself, him, and my younger brother from then til now (except now, thanks to my education I do know Spanish fluently).

However, that didn't prevent me or my brother from understanding the hatred he had toward us, even as children. He would yell, cuss us at us ( a 7 yr old and a 3 yr old), get drunk, smoke, he was just awful.

Things got progressively worse. Throughout my childhood I had to call the cops constantly, and cried myself to sleep so much. Once he even tried to run my mom over with his work truck and drive into the house.

The thing I don't understand is my mom is a SUCCESSFUL and beautiful woman. She has a very important position for the state; and is educated. The man doesn't have a stable job, and never has. He works little side jobs putting down tile, and gets drunk every evening.

However she WONT leave him. She says she feels sorry for him which I don't get! She says she can't just "kick someone out"

And if he ended up in the street she could not live with herself.

One of the reasons I didn't leave to go to college was that I was scared that something bad would happen to my younger brother or my mom. Once when my brother was 15 my stepdad tried to get him to "fight" him. Since then I've been scared that he would hurt him.

Not too long ago my stepdad picked an argument with my brother and tried to intimidate him by getting into his face. I lost it completely out of fear something would happen to my brother. So my 5'3 120 lb self began swinging at my stepdad. I actually ended up hurting him, even though he's much bigger than me. Everyone is in shock, I don't even remember it happening, and I do regret it. It's so ugly that I did that! but I was so scared that something would happen to my brother.

What made me SO angry is my mother got mad at me! He was going to hurt my 17 yr old brother and she got made at me for protecting him. I didn't understand her reasoning, the man has abused the family his whole life, and could've hurt her son, and she gets mad at me?

So recently things have progressively become unbearable. His family leaches off my poor mom all the time, coming and going as they please, and he keeps trying to argue with me. He tells me I'm nothing but **** and won't amount to anything(even though I've worked several jobs and internships and have gone to college)

He never has EVER helped me with anything financially and doesn't pay his way at home either. Waking up in the morning, I'm used to the thick air and awful Ora in the house. I've gone through depression, eating disorders, I've had a lot of personal problems throughout my life due to his ****.

I truly believe he's only here because my mom takes care of him, and he probably is hoping to get something monetary if anything were to happen to her in the future.

I've told her all of this and she still won't leave him. Anytime she's tried to, he BEGS to come back, and she falls for it.

Now that I'm graduating, I'm excited to apply for all these amazing positions,but I'm scared too. My brother is 19, fresh outta high school and barely getting started. I'm considering moving, out of state, possibly far away just to get away from him.

But....

I'm scared that this asswhole will do something to my brother, or hurt my poor mom. My mom is always so stressed from work, my grandma is in the hospital, and this man makes it 10x worse. If she ever had a heart attack I know it be from the stress he causes.

I'm completely caught in between. I want to leave- get away from this poisonous hell hole I have to call my home.

At the same time I'm afraid of what will happen to my mom.

How can I get her to leave him? Or what can I do? What about my brother?

Any advice would be greatly appreciated.