He simply nodded at her apparent happiness that Potter had won out in the end. What could he say? He still felt bitter about Harry and all he had accomplished (even if it was by luck rather than skill). It would take a long time for him to forget all the years of rivalry between them.
"Yes," he said. He thought the real reason his father had switched sides was to avoid Azkaban. Not that he would continue the acts for blood purity now that Voldemort was gone; father and son were alike in that they did not have the stomach for such horrible deeds, no matter how much they disliked Muggles and Muggle-borns. Draco was easing off the blood purity ideals, however, now that he had been away from his parents for a while. "Mum realized a long time ago that we shouldn't have ever been involved with the Death Eaters. She changed my father's mind too," he partially lied. "And Potter sort of... helped her, in the final battle."
Draco's face screwed up a little in confusion when she mentioned Horcruxes. "Excuse me?" he asked, thinking perhaps she had misspoken. Voldemort had never trusted him with that type of information. "Weasley's mother killed my aunt," he said, the bitterness returning to his voice. "I think one of the Weasley twins died. I don't remember which one." His cheeks colored a little; suddenly he didn't feel very useful, but he wasn't sure why that bothered him. It was nice of him to speak to Hermione at all, wasn't it? "And Crabbe died while he was trying to kill you, Potter and Weasley," he admitted. "I told him to stop, but he... his curse backfired. It was bad." His voice wavered a little as he spoke of Crabbe's death.