Taylor Swift thinks that John Mayer is "presumptuous."

The 22-year-old singer was outraged to discover that her ex-boyfriend assumed her 2010 break-up anthem "Dear John" was penned about him, but refuses to hear exactly what he thinks of her.

When quizzed about what John had said about her hit song, Taylor told Glamour, "How presumptuous! I never disclose who my songs are about. I know it wasn't good, so I don't want to know. I put a high priority on staying happy, and I know what I can't handle."

Long-haired lothario John - who is now dating Katy Perry - commented in June that Taylor's song "humiliated" him, saying, "It made me feel terrible. Because I didn't deserve it."

The blonde beauty is secure in her new romance with Conor Kennedy, but confessed she is not immune to criticism, let alone from her exes, and wishes she had a thicker skin. "It's not that I'm this egomaniac and I don't want to hear anything negative, because I do keep myself in check. But I've never developed that thick a skin. So I just kind of live a life, and I let all the gossip live somewhere else. If you go too far down the rabbit hole of what people think about you, it can change everything about who you are," she explained.