ok... Hold me Tight is likley a good text for you to read...
It does get a bit clinical, but I suspect you will like that.
If you compare your H in three time blocks
a. Pre-affair b. Affair c. His leaving and his affair
Has his anger changed in any way in these three time blocks? Was he always cold and critical like you describe him now?
I am trying to determine if he just has trouble managing his frustration with life's challenge sin general, or if this a mask to his hurt from the affair.
If he was warm until you cheated, I would suspect its just a mask to hide the pain.
Just talking about the affair isn't enough, it needs to be handled well... Hold me Tight again covers a lot of this... no point in typing out the book here...
But I suspect he needs to trust you again, and he needs to get past the betrayal's damage. If he keeps partying his pain is just going to fester and get worse until he wraps his car around a pole or something...
I am thinking a short speech like this :
I know I hurt you... And I can't apologize enough for that... It's an unimaginable pain. But you are doing this to me now and you aren't showing an ounce of remorse. We have a son and a marriage, and that's more important than how we have hurt each other. I just want us both to put the knives away and give us both some time to explore our marriage for our son and for ourselves. I don't want to fight you... I want to say I am sorry, and asking you to work with me is the best way I can do that... You are worth it...