I have a song, "East Looe Boys", which I try to sing as dispassionately as I think the fictional narrator would. The first few times I did it, I had to stifle a little sob in the voice, which would have been irritating for the audience. You learn how to handle these things by breathing properly and that sort of thing. At the end of the day, the audience wants you to tell the story rather than emote about it.