He's shut down compassion — how else would you become a Death Eater? So he suppresses virtually all of the good side of himself. But then he's playing with the big boys, as the phrase has it, and suddenly, having talked the talk he's asked to walk it for the first time and it is absolutely terrifying. I swear I never meant to let it die. I just don't want to hear it anymore. It's not fair when you say that I didn't try. I just don't care about you anymore.