John Mayer is opening up about his “humiliation” from an ex-girlfriend. You know, Taylor Swift, the bubble gum songstress Mayer dated two years ago. That relationship made a whole lot of sense, didn't it?

In an issue of Rolling Stone set to hit newsstands Friday, the 34-year-old singer shares his thoughts on Taylor’s 2010 single, “Dear John.” It doesn’t take a sleuth to figure out the song was about Mayer, and now the “No Such Thing” crooner is speaking out.

“It made me feel terrible,” he said. “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 to do.”

We’re assuming Mayer’s referring to the line in the nearly-seven-minute-long-opus that takes an accusatory hit at the couple’s age difference.

“Dear John, I see it all, now it was wrong/Don’t you think 19 is too young to be played by your dark twisted games, when I loved you so?”

“I will say as a songwriter that I think it’s kind of cheap songwriting. 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 bulls**t.”

Right, because John Mayer never made a career out of exploiting details of his relationship. Jennifer Aniston, Jessica Simpson, care to comment?

To be fair, Taylor’s been no angel. There’s some nonsense about the inserts on Swift’s albums and decoding messages and the CMT Awards, which would take a sleuth to figure out. Suffice to say, after the breakup the teenager acted like…well, a teenager.

Still, we’re sorry John got his feelings hurt in the business.

“I never got an e-mail. I never got a phone call. I was really caught off-guard, and it really humiliated me at a time when I’d already been dressed down,” he said, referring to his musical hiatus following notorious interviews in Rolling Stone and Playboy. See question above regarding Aniston and Simpson.

“I mean,” Mayer added, “how would you feel if, at the lowest you’ve ever been, someone kicked you even lower?”

We’d feel like writing a song about it, naturally. JM’s new album, “Born and Raised,” is in its second week at the number one slot on Billboard’s top 200. Hopefully that fact is making him feel better about the whole situation.

Watch Taylor’s homage to John below as well as “Half of My Heart,” the song the duo collaborated on together before things went south. Strain your ears just right and you’ll hear Swift’s twang in the background.

J-Connection: John Mayer’s father is Jewish and he’s said he relates to Judaism. However, it’s clear he’s got a thing for shiksas.