I always thought that the song was about someone who had lost someone that they had been deeply in love with (either through death or a breakup). Because the pain is so great, she (I will go with the gender of the singer) has sex with someone that she does not love in a desperate attempt to feel good. In the short run, it works: she loses herself in the moment of carnal passion. However, once it's over, it only serves to remind her what she lost and makes her yearn for it all the more.
I always thought that the song was about someone who had lost someone that they had been deeply in love with (either through death or a breakup). Because the pain is so great, she (I will go with the gender of the singer) has sex with someone that she does not love in a desperate attempt to feel good. In the short run, it works: she loses herself in the moment of carnal passion. However, once it's over, it only serves to remind her what she lost and makes her yearn for it all the more.