So sorry to hear your situation, Pam. I feel like we have an awful lot in common -- the first and onlys, the complaints about underappreciation, the sudden move out, etc. Getting a bomb like yours is like a vicious punch in the gut, I know.
It is hard, horribly hard, but believe me, you do have the strength to deal with this. Do it for yourself, do it for your precious little girls. If you have to disappear into the bathroom once in a while to sob uncontrollably, do so, but then live life and do things to have fun with your kids. They deserve it and so do you ... no matter what happens with your H.
Good luck with this and keep coming back here often for support. It's invaluable when you're dealing with a hurt like this.