the song is very much focused on an abusive relationship, in which Florence, despite her lover's cruel nature remains infatuated, knowing that he was once a good man, but fearing he never was. She stays with him for desire to be with what he has to potential to be, she enjoys the idea of the relationship, yet she finds nothing from it (sweet nothing). Her lover has been abusive for so long, that she is insecure and can't let go (it isn't easy for me to let it go because I've swallowed every word).