I was just suddenly truck by the reason why Katara was able to forgive Zuko at the end of the Southern Raiders.
I always wondered how those things were correlated, in a way other than the fact that Zuko had been there for her. Because, clearly, Katara had already trusted Zuko enough to follow her on that quest. But I get it now. Her quest to face down Yon Rha was about detaching her rage and grief from what happened to her mother, from the way she looked at everyone from the Fire Nation.
Because look, Katara’s mother was killed by a firebender, from the Fire Nation, on a raid to her home. After that, she developed a hatred towards the Fire Nation. Not to that soldier specifically, but towards the entire nation, because she saw that one soldier’s actions as representative. The Fire Nation took my mother.
As she said to Zuko at the end of Season 2, she came to associate his face with the Fire Nation, and, subsequently, all the rage that she attached to that. But in this case, her feelings were exacerbated, because she had let go of that for a minute, and let Zuko in, and trusted him, and his betrayal then destroyed that tentative trust that she had extended. His betrayal led to Aang almost dying. It made her redouble her anger, and this time, it was specifically targeted at Zuko, for reinforcing what she’d already believed about the Fire Nation, that they’ll hurt you, betray you, take what you love away.
But Katara realised that that anger was eating her away, and it was buried so deep that she couldn’t just let it go. She needed closure on that. So she looked for the source of the anger: the man who killed her mother, and sparked this deep rage in her.
And what happens is that when she finally meets him, instead of being this towering, grim representation of all the cruelty of the Fire Nation, he’s simply an old man. A pathetic, lonely old man who she could break in half easily. In that moment, Katara is face to face with the reality of the situation: that her mother was a casualty of one man’s ignorant, cruel and selfish actions. Her death wasn’t some representation of the entire Fire Nation. With that realisation, Katara can let go of that roiling mass of anger. She can move on from that pain.
She doesn’t forgive him. Yon Rha is remorseless for his actions, his murder of Kya was, in fact, an act of pure cruelty in the moment. He doesn’t deserve forgiveness, and Katara will always, always be hurting. So she doesn’t forgive him. But she can let go of that blind hatred towards the Fire Nation. She can let go of that fear of being betrayed, of being hurt again.
And after this, she’s able to look back and see Zuko for what he truly is: simply another human being, with the same pain and grief that she experiences, someone who was there for her, someone who deserves her trust. Not some sick representation of the Fire Nation’s cruelty, not a constant reminder of what’s she’s been through.
So, she forgives him. Because it was her own struggle that kept her from accepting that he had changed. And she was able to move on, and be better for it.