Katy Perry, John Mayer Split Again In 'Hot N Cold' Relationship As Katy Fuels Taylor Swift 'Bad Blood' Feud [Video]

Katy Perry, John Mayer, and pop singing stardom. That sums up what's made the "Hot & Cold" couple's antics so entertaining. Round One: Katy kicked off the romance, then Perry kicked out John. Mayer made the move, then broke up with Katy in round two. And it's still the same old story as Perry and John reunite, then separate, reported E News.

What's the latest in their relationship? Katy has decided it's time to break up after the most recent make-up. Perry and John may reunite soon, but for now, Mayer - judging from his past posts after a split from his off-again-on-again gal pal - reveals that he's emotionally miserable.

"I wouldn't feel right posting anything else before saying my heart hurts today."
In contrast, just as with Katy's own song, "Hot and Cold," Perry apparently is putting her heart on ice, since she hasn't revealed any heartache of her own.
Instead, she tends to take a more esoteric view of love.
"The bad news: there is no key to the universe. The good news: it was never locked."
However, John was seen cuddling with his 30-year-old girlfriend during the Fourth of July holiday weekend. Mayer and Katy were casually close initially at the Grateful Dead farewell concert series in Chicago, reported People.

"They were backstage being super sweet together – but not standing too close – in a big group of friends," revealed an eyewitness. "Someone handed her a tie-dyed rose. Katy was extremely polite, gracious and friendly."

But then Perry was spotted giving an enormous hug to John, who is 37. And their PDA continued throughout the concert series.

"They were holding hands backstage Sunday," added the observer. "For a short time, they were in the pit, but then the spotlight went on them, so John grabbed Katy's hand, pulled her out and they left."

The history of Perry's and John's relationship began in 2012. Mayer and Katy stayed together, then split, then made up, then broke up again in 2014.

And Perry isn't just in an off-again-on-again relationship with John. In addition to Mayer, Katy has become known for feuding with Taylor Swift, as the Inquisitr reported.

Perry reportedly has been contemplating the best way to respond to "Bad Blood," which Taylor is rumored to have directed at Katy.

Taylor once revealed that "Bad Blood" told the tale of her views on a female performer, terming them as "straight-up enemies."

And now, fueling the feud, Katy decided to offer her views on Swift's feud with Nicki Minaj, reported Digital Spy.

"Finding it ironic to parade the pit women against other women argument about as one unmeasurably capitalizes on the take down of a woman..." tweeted Perry.

Katy apparently is targeting Taylor, going back to the "Bad Blood" song crafted to the meltdown of Katy's and Taylor's friendship.

[Photo by Alex Wong/Getty Images]