It's all in the choices we make.
He looked down at his enemy, bleeding and torn from the spell damage that had been inflicted on him – Blasting and Cutting hexes, a Bone-Melting curse that was probably from Snape who lay not too far off. What remained of him, anyway.
Defiant, angry eyes glared back at him, a snarl twisting his enemy's lip expressing the hatred that he couldn't gather the breath to voice. Yet somehow, looking at the man his enemy had become, all he saw was a lonely little boy who'd never had parents and had never really had anyone who loved him. For all those who'd claimed to be his friends or claimed to serve his cause, it was bitterly ironic that it was they, as enemies, who understood each other best.
He wondered briefly, if the other regretted that it had come to this, the two of them drawn together by a prophesy made by a drunken old bat, who even now cowered in her tower, ready to hang herself if the battle went ill, both terrified and elated that it was her words, her power, that had brought about such a battle, the likes of which hadn't been seen in centuries.
The din was dying down now as it mimicked his own confrontation in an absurdly poetic fashion. He could hear the thoughts of the dead, and the dying, as easily as he heard the unspoken thoughts of the living, though none were near enough to actually voice them. The combatants had all quickly learned to stay away from his personal battle. No one else was strong enough or powerful enough to last.
Briefly, he scanned the field, eyes unseeing even as they fell upon familiar faces – Malfoys and Weasleys, Lupin, Pettigrew, Bellatrix Lestrange. So many had come and fought and suffered and died. Even for him, far too familiar with pain and suffering, torture and death, the scene was unimaginable. When he'd first set foot upon his path, he'd never dreamt that it would lead to this.
He sighed, looking back at his enemy, knowing resignation, even understanding were mirrored in their eyes.
"Strange," the man croaked, spitting out a bit of blood, "in this moment, we know each other better than we did in ten years of conflict."
"Do you see yourself here," he asked in reply, "even as I see myself there?"
Eyes closed in silent reply, and he raised his wand once more, words on his lips. "Avada Kedavra," he said softly, watching the man relax into the embrace of death, one that he'd probably wished for so many times.
Slowly, he considered the thought, then turned his wand towards himself. It would be nice to finally relax, he thought, even as he whispered the words again.
After all, it was simply a matter of choice.