When my W told me she wanted to move out last year, we could talk very well like friends. Maybe once decision is made, you feel better. But my W cancelled her moving out. It have been 3 times now.
I think it is good for your H to live alone for a while. It certainly make him misses you and family more. When he is back, he will appreciate more what he was missing.
My W left only for 9 hours. Not long enough for her to miss the family. So she still isn't committed to work on out R. She is lingering on her depression and MLC. See from positive side of your situation. I do believe your H has not made up his mind yet. It is hard to leave the family. Otherwise he would have told your kids about it. He felt guilty. He needs to work on himself and find out his true feeling. Then he can works on your R.
Try to live your live to the fullest without H. Don't give up hope yet. I'll pray for you.