See, I can't help but think that the threatening to break up thing was in response to DD never shutting up about this to Julian. I doubt DD saves his 24 hour mania exclusively for streaming. Imagine falling asleep to someone bitching, then waking up 8 hours later to that person STILL bitching about the same fucking thing.
DD tends to steamroll Julian when their opinions don't match up. They streamed Night in the Woods and Julian was almost desperate to get DD to stop shitting on it. "I REALLY wanted this to be good!" "The artstyle carries a lot of this." "You always want indy projects like this to be good." It's a small example, but you can find a lot of them over the years.
My take is, Julian is depressive and DingDong is just miserable. With other people, Julian would be better. He laughed that hard with Chris because there's not much laughter in his life in general. Dude's got some issues and constantly being reminded of how shit everything is, no really, LOOK at it, how can you tell me you like something like this??? is tearing him down.
There's no hope for DingDong. He's bitter and miserable and he actively tries to make everyone feel the way he does because he's "right" about every flaw and imperfection, and how could you like something flawed or imperfect??
Julian doesn't have anyone in his life but DingDong now.