I'm sorry if I came across as being glib or dismissive when I said run...I certainly didn't mean to suggest that anything about this is easy. Of course you are sad, of course you are worried about how your children will react...and since you are a giving, kind person, it can seem easiest to just continue to sacrifice yourself for their sake.
But here's the thing...your son will grow up and repeat the abusive behavior. If you have a daughter, she will grow up and repeat the victim pattern. It happened in my family...we're all still dancing around my father's moods and he's 90 years old.
I wish you well and admire what you've accomplished. If you can get through nursing school under these circumstances , you can do anything.
Sending you a hug.