I'm going through a similar situation right now so I feel for you. I am 31 weeks pregnant with our second child and we have a 2 year old DD. H and I had a big blow up about two months ago and he has been fighting for a divorce while I've been fighting for our family. Right now, we are separated, but my H refuses to go to counseling and doesn't seem willing to work on our marriage so I believe we are headed for divorce.
It's really hard but everyday gets easier. I am just trying to focus on my children and keep myself busy with friends and work as much as I can. I have cried a lot but right now, I'm just letting myself be numb. I think that's okay.
If you have family and friends nearby, lean on them as much as you can. Ask for help when you need it, even if you're not used to having to ask.
So sorry you're going through this. I wouldn't wish it on my worst enemy.