This is...sort of a songfic. It's WAY more fic than song and the lyrics could also just as easily be Katara's thoughts. But still, just to cover my ass, the lyrics officially belong to The Fray.
Where did I go wrong?
Maybe on second glance, things had seemed itoo/i perfect that day. Everyone was getting something they wanted or needed, Appa was back, they'd finally gotten rid of the Dai Li and spoken with the Earth King.
"Of course everything would suddenly fall apart," Katara whispered. Tears filled her eyes as she looked down at Aang's prone form.
I lost a friend
She kept reliving the moment in her memories. Aang closing himself in a crystal tent, concentrating, glowing, rising into the air. She'd never felt prouder of him than she did at that moment. Then the lightning striking his back, Azula's gloating smirk, Aang falling, falling...
Somewhere along in the bitterness
Zuko betrayed them. She...no, his uncle, had almost gotten him to join their side, maybe he wasn't such a terrible person, but he chose his sister. It was all his fault...maybe, she didn't know. Maybe him joining their side wouldn't have made any difference and Aang would still-
"No." Katara clutched his hand more tightly, tears streaming down her cheeks. "He opened his eyes when I used the Spirit Oasis Water, he's still alive."
And I would have stayed up with you all night
She laid down beside him, wrapping her arms tightly around him and burying her face in his shoulder. He was alive, his breathing was shallow and he was still so badly hurt, but he was warm and alive and they were together.
But still...what if things could have been different? What if she'd somehow been able to protect him from the lightning, or she'd been able to stop Azula and her friends before their takeover of Ba Sing Se, or...
"I wonder if we should have come there at all."
Had I known how to save a life
Katara closed her eyes, letting the shallow sound of Aang's breathing lull her to sleep.