Disclaimer: I do not own Harry Potter. Only in my wildest dreams. Probably not even then.
He had emerged from the battle unscathed, with Lord Voldemort gone, never to destroy a life again. He was gone, the one that had controlled their lives, that had influenced everything they did, every choice they made, and every thought that had entered their minds. Gone. Forever.
But though Lord Voldemort was gone and could no longer desire to influence actions, choices or minds, the fact that he had once been able to would never leave those who remembered. And the case was no different for Harry Potter, the hero who had saved them all.
The story of the final battle was a mystery to all those who dared to wonder. No two tall tales would ever be quite the same. It was a favorite legend as well, reenacted by wizened old warlocks over a firewhiskey in the Leaky Cauldron, by mothers chatting animatedly together as they watched their children embark from Platform Nine and Three Quarters, and by Hogwarts students of all ages when one had a desire to tell a particularly thrilling tale. But one thing was unwaveringly agreed by all: the famous Harry Potter had emerged unscathed.
However, Harry himself knew otherwise. Yes, he had defeated Lord Voldemort and had come out of the battle standing tall and not having shed a drop of his own blood. But scars were not always visible. He had seen his friends being tortured, unable to interfere, seen the blood that could flow from a person's body, and he had seen death, seen the lights leave the eyes of those he loved. And he had to live with the consequences of that battle, which would haunt him forever. No longer could he enter the Hogwarts castle and remember how happy he used to be; that happiness had been seized from him, and the sadness would always overshadow those blissful memories. No longer could he even look at the photographs, they were cruel reminders of his past, smiling and laughing back at him, unaware of their impending fate.
But he had no other choice but to do it, to kill him. People saw it as bravery, as moral, as heroic; they saw it his duty, his destiny, the burden he had been given the night that he was also given his scar. But it hadn't been any of those things. It had been a hunger for revenge. He wanted to guarantee that the man – no, the thing – no, the murderer who was responsible for his broken life, and the broken lives of many others, paid dearly. And his debt would be paid when he was faced with what he feared the most, death. So now that nothing more could be taken from him, Harry Potter clung to what he had left. He clung to what he had fought so hard to save, the fragments and shards of his broken life. He pieced them together, tenderly and resolutely, knowing full well that once put back together they would never bear even a slight resemblance to the colorful beauty they once displayed.
So the rest of the world continued their lives, safe and content, without a care. But not Harry Potter. He lived in his memories, the happy times that could be no more. And when people looked at Harry Potter, they saw the hero, the one who had saved them, not the tortured soul that the saving had forced him to become. So people thought that he had emerged unscathed, unscathed except for his famous, lightning bolt scar.