If they really can't even see that someone can care, then it certainly sounds as though the problem is in their understanding rather than your explanations. The viewpoint of "I don't care what happens if it doesn't involve me in any way" doesn't seem in any way inherently self-contradictory, so it'd be a hard position to argue against, but that shouldn't be getting in the way of seeing that not everyone has to think that way. Things like these three comments might have a shot at bridging the empathic gap, but if that fails... I got nothing.