I agree for the most part. Maybe he knows he's lying to himself, but it's something he can blame that's not on him.
I think his final fallout with Jimmy is what caused his relapse. When Hamlin came over earlier in the season to tell Chuck that Jimmy was getting 12 months suspension, this was a good thing, and that Chuck should move on....that's when Chuck did a toast to new beginnings I think. That's when he started to improve. He'd moved on from Jimmy's shenanigans changing the addresses. I remember trying to figure out when Chuck started to get worse when I I re-watched season 3 last week.
I didn't remember seeing any on screen clues that he was getting worse until Jimmy came over to Chuck's house to try to apologize in the season 3 finale I think. Chuck had music going throughout the house and he had lights on. Seemed pretty comfortable. Chuck basically told Jimmy don't bother apologizing, it's not worth it because you'll keep hurting people, and that's when Chuck told Jimmy "I never really cared about you anyway." Jimmy walked out saying nothing I think.
Later in the episode you see Chuck wake up early morning and write down in his pain journal that he was hurting. After that in the episode is when he's going through the house trying to find what's drawing current, calling the power company, and ultimately punching holes in the wall.
If you're a detail stickler like me, I paused it earlier in the episode when he was in bed to read his other journal entries. The one before, his mood was "agitated". I think that was when Jimmy came over earlier in the day.
Now I want to go back and re-watch Hamlin's confession to see and hear the exchange again. Maybe it contributed some, but Hamlin and Kim seemed really surprised that Jimmy would just accept his statement. "That's your cross to bear." Like he was happy someone else would carry that burden.