I really like the idea that when Gamzee was being a horrible moirail, he just stopped talking to Karkat altogether. As someone who used to pull the silent treatment when I got stressed when was younger, I can say that it can be really upsetting for people, even if you’re not actually trying to hurt them. And man, Karkat. With everything he got put through and then having to pull all the weight in a moirallegiance, I can really see that period where he was still trying to make it work (and where Gamzee just didn’t care) being the most horrible, awful thing for him.