Weekly prompt #4: Fire
Sometimes he couldn't even look at fire without feeling sick. Every time he did he remembered how his careless stupidity had hurt the person he cared about more than anything. When he shut his eyes, he could still see himself happily flinging the fire, Katara holding her hands up to protect herself. Katara sobbing, Sokka's anger, the sick feeling of remorse.
Katara had forgiven him and so had Sokka, but even now he couldn't fully forgive himself. He'd hurt her, he'd hurt the first friend he'd made since waking up from his century-long nap. Every time he saw fire he saw his mistake and everyone he knew shouting blame at him. Idiot, this is all your fault!
He had to learn Firebending in order to defeat the Fire Lord and save the world, he knew this. But Jeong Jeong was right, fire was synonymous with destruction. A great power, but in the wrong hands a threat to anyone and anything.
Zhao knew it and took advantage of it to hurt people. Jeong Jeong knew it and swore never to bend again. And now Aang knew it, but he didn't know what to do. If he didn't learn Firebending he'd never save the world, but if he did, there was always a chance he could hurt someone again.
He stared into the campfire's flames, feeling sick and guilty and seeing it happen over and over again. Katara's hands, Sokka's blame, Zuko and Zhao using their fire to harm.
Fire is pain and destruction.