I am writing a character who is sort of a sociopath, but he isn't. He's a sociopath in that he doesn't feel guilty for what he does. He is unburdened by second-guessing himself. But at the same time, he's not unsympathetic to those around him, he does not lack empathy. He's not cruel, but if the circumstances call for him to do something drastic, like kill someone, he will do it without hesitation or remorse. He will be philosophical about it, and think about what he has done, but he does not feel guilty for it. In a way he is completely and totally alienated from society, but he is ok with that. He accepts it as his lot and doesn't navel-gaze.
Is this kind of character even realistic? Or are we conditioned to think that people who are not saddled with guilt are sociopathic? Is there some underlying assumption in our culture that guilt is moral and healthy?