At this point, it's probably a defense mechanism. Can you imagine the kind of soul crushing realization it would be to accept that you're responsible for your spouse's death because you got way too deep into shit posting on Facebook? It's way, way more comfortable to displace that blame and rationalize it away.
I sort of feel like the exceedingly casual posting on Facebook about this very world-wrenching moment in his life is proof enough for me that he's made a few horcruxes in his time and has a maimed soul.
If I was in his shoes, those 3 words would be on loop in my head, and I'd be curled up in a foetal position bawling, insensate, forever. Like the end of a particularly disturbing Black Mirror ep.
Yeah, he probably does. In between the space of consciousness and unconsciousness, when the frontal lobe can't run defense anymore and the limbic system starts to lose its weighted clothing, it probably sneaks through. Probably right before he goes to sleep, or in his dreams, or when he's spacing out on something, it sneaks up on him like the cat in the hat with a bat.