It sounds to me like she broke up with somebody who she thought she knew, but really didn't and now he's like an actor out of work. He makes her feel better and she wants to be with him but she knows she shouldn't and that she can let him go. (You're a supplement, you're a salve/You're a bandage, pull it off/I can quit you cut it out). She's still in love with him, and for that she thinks she's mad.
It sounds to me like she broke up with somebody who she thought she knew, but really didn't and now he's like an actor out of work. He makes her feel better and she wants to be with him but she knows she shouldn't and that she can let him go. (You're a supplement, you're a salve/You're a bandage, pull it off/I can quit you cut it out). She's still in love with him, and for that she thinks she's mad.