Ok just a second now I need to headcanon about really sad things
So the way I read the Zuko/Katara relationship as a friendship is that she is the replacement of his mother. There is no way Ursa’s quote about turtleducks wasn’t thought of when Katara issued her threats to Zuko; plus, he just takes the abuse, because it’s like he’s being scolded by a mother. If anyone else said the same to him, he would’ve probably snapped at them - but he’s experienced his own mother’s sacrifice for her child first hand. He knows Katara isn’t fucking around. She would sacrifice everything to take care of her family.
And he wants that protection/love. So their whole relationship arc is based on their mothers, on family relationships, on revenge and restoration for what they’ve lost. They really settle into a strong friendship. And since Zuko is older than her, he’s stronger now, he feels that there is some level of protection that he can offer her as a friend. Katara of course hates this but waddaya gonna do it’s Zuko.
So when Katara is dying and Zuko visits her, he’s a wreck. He was a mess at every funeral and he did not. give. a. shit. if it stirred whispers up when the Firelord showed up, unabashedly crying at the funerals of his closest friends. They were his chosen family, the ones that accepted him for the person he was and ultimately became.
But he’s got what, two years on Katara? She’s the healer. She’s the one who, in his eyes, should outlast them all, the one who watched over everyone and made sure they were all ok. She should usher them all off into the Spirit World and then come last, where they’ll greet her and be a family again.
Zuko would cry and say that he doesn’t want to be alone again. It was unfair enough that his friendship with Aang was cut so short after struggling to learn why their destinies were intertwined.
Oops I made myself sad.
THANKS FOR THE PAIN, HANNAH. YOU MONSTER.