Aww DejaVu, my heart goes out to you; I can understand how devastating that was to hear. This weekend my H has told his father that he lives elsewhere (father left a message on the ansaphone asking me to ring him) and it is a major step forwards for our S that he has done so. I'm not going to ring him because I know I will get all defensive as I doubt very much he has explained the full situation. I don't need to go looking for upset.
My opinion, for what it's worth, is that you are still struggling to detach because you are such a nice person. I think that you put the kids first, then his needs, then yours. As a mum you will always put the kids first but I still think you help him out too much in his situation.
Of course you cannot understand how he has done some of the things that he has done. None of us can understand it because we are not him. We don't need to understand it; he does. It is the reality though. It has happened and trying to understand it will keep you stuck in the past. You are comparing the past to the future and that leads us all to have fear. It'll be different, it may be harder for a while, but new things can be exciting and fulfilling.
I'd bet my bottom dollar that if you had an accident and lost a limb; you wouldn't wallow in self pity, you'd get on with your new reality and make it work. Because you are strong. It wouldn't change the fundamentals of who you are; you would be just as strong and successful but you would have to alter how you go about things.
If D did result from this then you would have a 'business' only arrangement with him. The only 'business' you have with him at the moment is the kids. He appears to be stepping up to the mark regards the kids, so let them get on with it. I think at the moment he sees and has access to the whole package when he wants it - wife and kids. He has not yet experienced what it feels like to be a divorced Dad.
Show him. Stop being a wife and become a polite 'business partner' If you see him every day, that's fine because you would see a business partner most days. Don't help him out by sending him nice texts about the kids, photos etc, he will have to create his own.
Is there something you could do to occupy yourself when you are on your own? I separate GAL (external) with self improvement (internal) in my head because sometimes GAL activities are tiring when you work full time and expensive. Is there something that you've put off doing because you are busy with the kids? An online course, reading, tapestry, cross stitch,knitting, a box set on TV that you've been meaning to watch. Something to make you concentrate and keep your mind occupied. Something that you will appreciate that you now have time to yourself.
A very good friend of mine gave me a stern talking to last week when I was upset and worrying for him and his future. He really has to stew in his own juices and realise the consequences of what he has done. I have no influence over whether that even happens BUT I shouldn't see this as the end of something but as the beginning. If he comes back, and we remain married then it's the start of a new marriage, if he doesn't then it's the start of a new me regardless.
I have to stop thinking that he's going to come to his senses and I tell myself daily that he isn't and force myself to do things as if he isn't eg packed his clothes into bin bags yesterday. Some days I have to fake it, but it is getting easier.
I have this little voice in my head that says that my detachment means that I have made it easier for him. But then, if my actions made his mind up for him, then he obviously wasn't prepared to fight for the marriage and doesn't want to be here.
Stay strong DV6 and find your selfish side a bit. Try to think 'I' thoughts not 'him' or 'we'.