What I take from reading this is that people in a relationship wear mask and hide their true selves from each other. Eventually, those mask or layers are removed and the true self emerges. The relationship ends and neither person really understands or knows what or why it happened at all. The last verse is the one that I like the best.

Suddenly the dance no longer ever after
The dragon laughs as he rips her heart out
The bride draws her sword and slits her master
Neither knows what the dance was all about

Nice job comparing love to dance.