Hi Solost
just checking in on your thread , maybe its the spring with all those birds and bees doing their thing as I have been feeling very much on my own too which I havent really since my h left last christmas.
Also the constant insinuations from your h that BB isnt all he thought and that he has regrets must make it hard to detach. My h claims utter happiness with his ow and has no regrets about leaving which of course to begin with was very painful but for the best as I never ever thought he would be back to us.
I am moving in 4 weeks time all being well and thankfully I dont feel emotional about it its just something that has to happen. I am lucky though that my new house is really lovely and in this area still.
I am initiating the divorce and h is fully on board , as you might remember we sorted out finances etc a while ago, so it should be quick and painless. I am at the point where I just want all the nastys possible to be out of the way iyswim ?
Do you still think he might come knocking on your door Solost ? I wonder if when the issue of where he is going to live long term arises and he sits and does his sums the full reality will hit him ? Not that I am suggeting he would only want to come back for those kinds of reasons. I really dont envy you this situation of being fed snippets of his doubts about what he has done . Its like well Solost if you sit patiently and serenely high above while he and BB scrabble around in their little emotional drama eventually he will get it out his system and realise how foolish hes been and come back home.
The thing is everyone is right despite anything he says what he does is to remain with her.
I would really think about starting the divorce because I doubt he will anytime soon and assuming he doesnt do an about turn at that point you will then know that your marriage is over and can carry on further down the road of recovery. I think as things are you are in a bit of limbo and however small a part of you still hasnt given up hope which is entirely understandable after such a long marriage etc.
Overall ask yourself do you still want to be in this position with him a year from now ? If the answer is no then make a start because these things take a long time 
You are doing brilliantly Solost like so many of us who have been left with dc after long marriages while they trip off with ows but we are doing ok and are/will be happier in the end 