Lyric discussion by mockingsmile 

this is such a horribly sad song. here's what I think:

the first verse is the only part that talks about the girlfriend as she really was. She really did love the guy and make sacrifices for him. In this verse, he says that she "squirmed and turned like a skeleton key." Squirm has connotations of eagerness and sexuality, and given the context (a list of nice things she did for him) I think "squirmed and turned" means that she would do anything to make him happy sexually. Like a key, she'd do anything to "fit" what he wanted.

But the guy didn't think she really loved him. This was because he was insecure, but he blamed it on her, saying she really didn't love him. ("My dire affliction I'll attribute to you.")

The next time he calls her "the skeleton key," it's very different. It still has sexual connotations, but it says "twist and turn" instead of "squirm and turn." "Twist and turn" sounds more sinister, and "you're finally free" makes it sound like it's something she can't do while she's with her boyfriend. So instead of meaning "she'll 'turn' (change herself to please me sexually)" the line now seems to mean "she'll 'turn' (move from guy to guy)." The guy takes something nice the girlfriend and did, and twists it around so it makes her look bad.

He convinces himself that she's unfaithful, and says "You've gotta let me know [that you're cheating]." But she really isn't.

The guy "bred his misery" because he caused himself to be upset about something that didn't even happen. Because he was upset, he took it out on his girlfriend, which made him feel better but hurt her.

Presumably, they break up. Later, the guy knows that she really didn't cheat on him and loved him--at the beginning of the song he says he did "a sick, sick thing" and blames his "lack of loyalty," not his girlfriend's supposed promiscuity. However, he distracts himself from his guilt and sadness by drinking whisky, and when he's drunk he's able to blame his girlfriend again. "You're nothing special... you're a skeleton key [a whore]...You've gotta let me know [if you cheat on me]."

Usually I'd feel dumb for writing such a long post but I'm not the only one who did.

oh, i totally agree with this interpretation. i just wrote something similar before i read this.

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