It's not that uncommon for a trad song to change person, e.g. "A blacksmith courted me ... her lips grew pale and wan ...". It's a nice litereary device for a number of reasons, not least is that it enables me (a man) to sing a woman's song. But(oops -- grammar!) it also allows the singer to slip into the present tense and increase the drama -- "it's happening to me, and it's happening now". When you get to the end, you "reveal" that it's a story after all, and you leave your heroin trembling with fury but you don't say what happened next -- just like a modern short story.

Steve

P.S. But there's no excuse for swapping between "You" and "Thou"!