It's about alcoholism. "With an heavy, heavy heart and achin' pain" They might as well have said "achin' head" sing "pain" and "again" don't rhyme with an American accent. "I'll not leave that las again." I found the same thing on other lyric sites, not "lass." Where do these lyrics come from? Listening to the Brothers Four version of this song, it sounds like "glass." "Come all you lads where e'er you be" What makes more sense, that many lads from all over could be tempted by one girl, or all be tempted by their local bar? "So many men was hoardin' Nancy" Admittedly, "hoardin'" is a strange word to use for either a girl or booze. I heard it as "courting" which would apply better to a girl, but maybe to a drink, too. "Never lose your heart to Nancy She'll ruin you as she ruined me."