Another Yue headcanon:
She was betrothed to Hahn the day after her 16th birthday. NWT is not a medieval Europe (some Venezia touch doesn't count) to engage literal kids. But 16 is a coming-of-age, the person could be married, the avatar could learn about being the bridge between humans and spirits etc.
That also explains Yue's inconsistent mood. At her birthday party she clearly flirts with Sokka, as well as the morning after. She has a very strong sense of duty, she'd never do this if she was engaged. But what if she was free back then?
It all changes in the evening at the bridge. She's sad and cold. She can't say Sokka what's wrong now – because she is engaged for less than a day, her life has changed completely and too quickly. She is confused and feels guilty for giving Sokka the wrong impression she could not turn back.
Poor girl.
As I said – my favorite characters suffer because I love them.
Id in ALT
