One of the things that really gets me about The Southern Raiders is when you realize that after their trip, they didn’t go back to the camp. Zuko took Katara directly to Ember Island (
she’s already there on the beach, when the others fly in). To the place that we know was so special for him – where he felt his family was actually happy. Zuko choosing Azula’s side in Crossroads of Destiny is motivated by that last bit of hope that he could go home, that his family could be whole again.
It’s in The Beach, coming back to the summer house where he finally is ready to face the truth that things will never be the same, and he kind of lets go of that dream (we never see the Ember Island memories again). But also Zuko realizes that he’s been projecting his anger at himself about his betrayal at others.
I think Zuko brings Katara here, before the rest of the group, to give her space to sort through her feelings herself (
without anyone telling her what she should feel). And she comes to similar realizations; that her anger at Zuko has nothing to do with her mother and that she’s ready to let go of at least the part of the anger that she was projecting at him (and forgive the very real grievance she has with him instead).
Katara’s forgiveness is the last step for the Gaang to truly become a family, and I just love the symbolism of it happening in the place that Zuko considers home. And there is all the added beautiful parallels of Katara with the sun and Zuko with the moon, and Zuko getting that exact shoulder touch he’s dreamt about during his exile from Katara.
And just as Zuko finds the Avatar in a completely different way than he expected, Ember Island becomes home again, but instead of going back, they move forward, building something new on the ashes of past traumas.