CK, I think you are right - you are going through exactly what a lot have gone through. Doesn't make it better, but know you are not alone. Try to stay away from getting other family members involved. It will not work out well. I've had the same dream in the past. Very similar. But I have come to realize its because I have a ringside seat to the train wreck. What comes across to me in your posts is that your H has a lot of fixing of himself to do. That will take a lot of time. Him reaching out to the kids is not a bad thing. They need that and so does he. If you get them involved, that will short-circuit the relationship he has with them - that would not be fair to the kids.
About you - Some believe that depression is the result of repressed anger. Ya think? I can see some of that being true. Find a way to safely let that anger out. Laughter is a great medicine. Exercise. Yelling at pillows. Etc. Try them and see what works. Make new friends. Get out even if for inexpensive walks in the local park. Explore.
The future - try to imagine it being really good. Do so without imagining H impacting it. If he is there later, it will be a delightful surprise. But imagine YOU happy. Practice that and your attitude will change drastically. Really. This is a long journey and it will take much time and you may be so wound up with anger by the time it starts to wind down that you can't take advantage of that. I've seen that happen many times in similar situations. Be careful it doesn't happen to you by taking care of you. You deserve to be the focus of your attention. And if you do focus on the positives, you will begin to change everything....
Keep at it. It'll seem awkward for a little while but it gets to be more realistic. And don't be surprised if H gets in your head from time to time. Just keep focus on you.
AJ
"Our lives begin to end the day we become silent about things that matter" MLK Put the glass down... "Yesterday I was clever so I wanted to change the world Today I am wise, so I am changing myself."