Re the last point... That's the one that hit me... You can talk about OW if he's willing... THAT is an opening.
And it is HUGE mistake to tell him she's irrelevant, in my opinion.
There are many experts in infidelity who argue until the third party/interloper is removed from the marriage repair is not possible... the OP needs removed before any significant progress can be made...
So, if your H presses you to talk about OW, I would lead with
We aren't going to make any progress on our marriage or with parenting our son while there is a third party trying to break us up... If you have any respect for marriage or our son you need to acknowledge the damage she's doing on a daily basis and send her away...
Or something like that to shake him up.. it has to be short and forceful... not pleading or critical
You are writing a lot about the negative stuff he's throwing around... DR makes it quite clear you need to ignore it, its just his hopelessness misexpressed... try to avoid taking it to heart... Its just chemicals in the brain out of balance ... it has nothing to do with you.
He's ill and he's not managing it constructively...
