There was very little that could truly break Harlow, and in the past even John's sharpest words-- no matter how much they hurt-- only sparked the fight in him. But this? This had nearly wrecked him. He'd spent so many years mourning John's death, and to see him there alive, to know he'd walked away from him, to know his own betrayal made him feel weaker than anything ever had before in his life. He'd hit some lows, but none as bad as this. He'd made mistakes, he'd done a thousand terrible things in his life that he should have felt guilty for-- but nothing was as bad as learning that he had left John behind in a building he set on fire.
At John's words, Harlow faltered, but how could he walk away with his chin up? Nothing could horrify him more than what he'd done.
"Don't tell me what to do," he snapped back at John instead, and kept walking.