Lyric discussion by tryptych 

MaxDG1013 above has the closest to how I feel about this.

It seems clear that one interpretation of this is an ode to existentialist thought, that ultimately the ground of being has no meaning, just like everything, like the fireflies fluorescing. Yet that meaningless allows love to be at all, it is beautiful/profound/infinite/magnificent and mind blowing.

Of course, at the same time it's simply an achingly bitter lament from someone who's just had their heartbroken.

The fact that it's both at the same time ably demonstrates Stephin Merritt's songwriting chops.

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