listen to this song. It has some interesting similarities to the set up of
The Wild Swans (the lover who betrays her is even named John, too)--sexual jealousy is at the root at it, too. Apparently, its inspiration came from the short story "Witch," written by George Mackay Brown. I've done a little work trying to run down the story. Haven't found a copy of it yet, but read a description of it, and, just in my version of
The Wild Swans,
the suffering of the heroine is clearly meant to echo the Passion of Christ.
Here's an amateur performance that's okay, that gives you the flavor of the song (the lyrics are in the side bar at the YouTube site):
But I really recommend, if you like what you hear, that you get it as sung by the woman who composed it, Karine Polwart, performing with her group, Malinky (buy it on iTunes
here. Karine's version is desperate and dramatic and tragic and heart-rending, and beautifully performed.