the main interesting aspect of Arin's character to me is not so much that he is a frustrated, angry, and lonely person underneath a kind, friendly, and eager exterior. Rather its that he is all of these things in equal measure, but everyone around him (including the audience at first) isn't really privy to these "negative" traits, and sort of has been brushing his expression of them off as simple lack of self-confidence; a small blip in his inevitable hurdle towards self-actualization. I don't think anyone means anything bad by it, but I think everyone views Arin as such an inherintly good and talented person, that he doesn't feel comfortable truly expressing how lost he feels without his parents. The dissonance is coalescing within him, into a guilt at not being good enough to save his parents. That causes the encouraging words of his mentors and friends to feel more and more like a lie, and those friendly and kind traits that are inherint to his character, to feel like a weakness that isn't even being returned to him in kind.