First time post for me, but I've been following this thread for some time so didnt want to lurk forever and wanted to give my thoughts from a mans perspective. I hope that's okay.
My overriding feeling through all of this is one of exhaustion, so I cant imagine how it must feel for you having to live it.
In short, it shouldnt be this hard. By that I mean, it shouldnt be such a huge struggle for this relationship to work - especially if both parties want it to work so badly.
I think the sad thing is that all the work, all the effort all the desire for a resolution is coming from you and you alone. Sure, you're in councelling together, but on your DHs side hes only paying lip service to it and I dont see any real desire to make meaningful change.
I dont like to say it, but if I'm honest I can see elements of myself in your DH. I am prone to sulking on occasion. It drives my wife mad, I know it does, and there are times when, yes, in my own little bubble, I'm doing it to punish her in some way.
Other times it's because I genuinely feel aggrieved by something that's upset me and (perhaps!) dont have the emotional maturity to vocalise it properly.
But this is the thing, on the occasions when I feel justified, I do communicate it (eventually!) and its resolved. BUT! In those times I'm being unreasonable. Deep down, if I'm 100% honest with myself, I know, I absolutely KNOW I am in the wrong.
In those instances it's the hardest to 'break the sulk' as it were - because I have to ultimately admit I'm in the wrong and it's my behaviour which is the underlying cause of stress.
Rewind 5 years or so, and my wife would have just waited out the sulk until things were back to 'normal' - but the underlying stress of it never goes away. Not really. Its insidious, builds resentment and causes further problems down the line.
The only way we broke that cycle is, not to put it too bluntly, was for me to just grow up a bit. To voice when I'm upset at the time and, crucially, for me to show humility and apologise when I'm in the wrong. And as I said, I ALWAYS know when I'm in the wrong. Any decently functioning adult does.
I feel like we've turned a corner in our marriage but that's only because my wife was as brutally frank about the state of play - exactly as you're doing.
Secondly, I had to admit to her and to myself that the behaviour needed to change. I needed to change the way I conducted myself when these flashpoints arose.
Looking back now, the ability to apologise when I'm in the wrong, communicate and resolve is actually quite liberating. Its removed an underbelly of stress that was always there. The relief in our relationship is palpable.
I guess the question for you now is, do you feel he has the maturity to admit responsibility for his own sulks and make the necessary changes for the good of your relationship.
Reading your posts over the months, it doesnt seem that way. We never went to councelling, we managed to work through it ourselves. The fact that it's gone so far and hes still firmly entrenched and deflecting blame suggests you're going to have a harder time of it than my wife did.
I hope you can get through this with a resolution which gives you both happiness and some much needed relief - because a happy, loving relationship shouldnt be such hard work.