I think you didnt understand his character, Juheon wasn't mad because his privacy was violated, he was mad because he has trauma of being used and left, he puts on a front to be liked but everyone around him either uses him of leaves, his mom, his step mom, his grandfather, his fake ass friends, etc.
he never had a healthy relationship where he felt safe being himself, and the one time he let his guard down he realized he was being used there too, imagine the self esteem problem and trust issues that would give you.
I don't think what Dohu did was a big deal, but that doesn't mean Juheon's feeling are any less valid
You have to understand juheon’s perspective as well, the crux of his trauma is that people only ever get close to him to use him you can’t blame him for not trusting dohu when the first reason he trusted him in the first place was because he thought he had no ulterior motive when approaching him.
All of that notwithstanding I do think him ignoring dohu so fervently has something to do with his aunt blackmailing him back in the end of season one
Dohu, I know you're neuro divergent and don't understand social norms much but seriously, he needs to not revolve around Juheon anymore because he treats him like ass over... Dohu obsessively writing about him and breaking down his character in college for a novel? (Personally, I would've been flattered but oh well...)
I know it's about Juheon's privacy and all but oh my god, that attitude is so not it. Anyways, I hope Dohu manages to use Jitae and screw both men over.