The Insider.com

John Mayer wooed Taylor Swift back in 2010, and inadvertently inspired one of her thinly veiled smackdown songs -- now, he's opening up about Dear John the first time in Rolling Stone.

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Of the track, which includes the lyrics "It was wrong / Don't you think nineteen's too young / To be played / By your dark, twisted games / When I loved you so" -- Mayer says he was "really humiliated." He adds, "It made me feel terrible. Because I didn't deserve it. I'm pretty good at taking accountability now, and I never did anything to deserve that. It was a really lousy thing for her to do."

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And while Taylor has never directly said John inspired the song, it's been long rumored, and seemingly confirmed given just how upset he is that Taylor never gave him a heads up. "I never got an e-mail. I never got a phone call. I was really caught off-guard," he says. "And it really humiliated me at a time when I'd already been dressed down. I mean, how would you feel if, at the lowest you've ever been, someone kicked you even lower?"

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But for Mayer, the biggest problem he has with Dear John is its inelegance as a song. "I will say as a songwriter that I think it's kind of cheap songwriting," he says. "I know she's the biggest thing in the world, and I'm not trying to sink anybody's ship, but I think it's abusing your talent to rub your hands together and go, 'Wait till he gets a load of this!' That's bullsh*t."

Somewhere, Jessica "Sexual Napalm" Simpson is smiling.