I think it's interesting how emotions pass around. We function within a social network, which is very sensitive and speedy in its transmission. I don't think that means we shouldn't share our sad feelings. In fact if we did limit ourselves in that way, it would wreck the social network itself, because it wouldn't really be about friendship any more. The research was very limited in its scope - it's interesting but I would hate anyone to think I meant anything more by mentioning it than 'well, fancy that'.
Perhaps I'm worrying about nothing, but it suddenly occurred to me I might have accidentally hurt someone's feelings, not for the first time.