It was never him doing all that damage, every time he was possessed by the Avatar State it was as if he was outside his own body watching someone else do it. Every time, he felt like he was drowning in a sea of violence he never wanted to create and when the dust settled, he was thrown back into his own body to gaze upon what he'd done.
It was like a demon sleeping inside him, rarely awakened but dangerous when it was. It didn't matter, the demon reasoned, Firebenders took your people. Sandbenders took Appa. Terrible people hurt everyone you care for and they need to be punished! No! his mind cried, the Avatar State was for good, to bring justice, not to hurt people!
"Aang!" She was calling to him again, like she always did. He felt her grab his arm, pulling him from the abyss back into reality and into her embrace. The rage subsided, the dust settled and he fell against her. "It's okay," she whispered, and he clung to her, only vaguely aware of the tears streaming down his cheeks.