I think this song is directed to another girl, not the guy she's interested in. She likes the guy, but he's already involved, putting her and the girl she probably doesn't even know at odds with one another. Since he picks the girlfriend, she loses which leaves her longing for him and a little guilty for "fighting" a war for him in the first place ("I never meant to be the needle..." sounds guilty to me, anyway). The song tells the girl he loves that she won, and that the singer doesn't really feel like she had a chance anyway because she's "not that hot new chick" that could actually win him away from the one he loves.
I think this song is directed to another girl, not the guy she's interested in. She likes the guy, but he's already involved, putting her and the girl she probably doesn't even know at odds with one another. Since he picks the girlfriend, she loses which leaves her longing for him and a little guilty for "fighting" a war for him in the first place ("I never meant to be the needle..." sounds guilty to me, anyway). The song tells the girl he loves that she won, and that the singer doesn't really feel like she had a chance anyway because she's "not that hot new chick" that could actually win him away from the one he loves.