Well, even I don't feel much if a distant relative or anyone I don't really know or care about very deeply dies. That's not abnormal. The difference is, I might act out a negative emotion, and try to look grudgingly accepting of the fact so that people wouldn't freak out as they did in your case, because I wouldn't want them to think less of me. I would feel a deep sense of loss if a person close to me died, and would come to always cherish their memory and past friendship, perhaps thinking of them periodically, wondering what they might say in a particular situation, remembering their previous ideas, opinions, and words. But I would probably keep on focusing on what I needed to do, and the people who were still here. After all, I know they wouldn't have wanted me to spend the rest of my life in sorrow over them, and that what matters and requires my attention at this point are the people I can still deal with, who are still part of my life. I might very well focus my attentions on comforting others.