WorriedNScared I am so sorry you're going through this 
I've just escaped an emotional and sexually abusive relationship too, I can completely understand how you feel.
It's ok to cry, it is ok to feel guilty, hell its even ok to regret it. You are safe now, that's a good thing. You will get your children back, don't worry too much, they'll be ok, kids are resilient. Women's aid are there to help if you'd like anyone to talk to about councilling etc, they can even help you with the legal process of getting your children (or at least give a lot of good advice about it).
I'm still in the waiting to wake from the nightmare stage too. It's awful, especially when you've no real support in rl. I'm just over a week into my "new life" and it's still not passed, still doesn't feel real. Wake up in the morning and everything feels fine until it all comes rushing back.
Be kind to yourself, remember that none of this is your fault. You've done the right thing, you've been so so incredibly strong to get yourself out and I know how much the need to break down can take over but don't give in. It'll pass eventually. I keep being told to give it time but no one is ever sure how much time, and really at this stage you just want everything over and done with.
Ignore anyone who doubts you, my exp is also a fantastic outstanding member of the community, loved by everyone while I'm the girl who has MH issues and he's trying to convince them that I'm throwing a strop because I didn't get my own way over something (he's never specified what) and we'll be back together soon enough (not happening). You've not over reacted (in case you feel like you have). Everything will be ok (at least, that's what I'm repeating daily, every time I feel like I can't carry on). It doesn't matter what he looks like to the rest of society, you've seen the real him. You found the strength to leave, you've found the strength to fight. Hold on to that, it does get better