Don't have to reply but want to. You hang in there sweetie. i feel so bad for you now. I don't know enough about your situation to help but I can say I care and understand what it feels like to feel lost, alone, scared, confused etc etc ETC.
You do what you know is best, one day at a time and things will fall into place. Your son is better off being in a stable environment without aggression and so are you. You will have time to explain and help him understand as he grows up. He may be confused now but slowly, someday he will understand and he will be glad that his mother got him out safe when he could've been damaged so much more. Also, he will look at his mother and know what a real woman is. Not one who takes abuse but one who is worthy of happiness and being treated like a woman. A good decent woman. That's you, you know!!
Heidu