See, this is what happens when people write a cheesy love song together: Katy Perry and John Mayer’s relationship is officially caput. At least that’s what sources have told E! Online. Neither singer has confirmed the breakup, which many are shocked about considering engagement rumors were swirling just days ago. The surprising breakup apparently had nothing to do with love or infidelity, but was all about business.

A source told the new site the “Prism” singer’s upcoming world tour has putting a strain on the former lovers’ relationship. Perry supposedly wanted to put her work first, but the insider didn’t mention if Perry’s hectic schedule was the final straw for their split. After the “Dark Horse” singer added another leg to her tour, she became booked from May throughout November.

On Twitter Tuesday, she shared that she would visit Australia and New Zealand in November. "PERTH, ADELAIDE, MELBOURNE, SYDNEY, BRISBANE! I'll be seeing YOU this November! Stay tuned for MORE info," she wrote, and added, "And don't worry, New Zealand... I'm coming to see you kiwis too! Dates announced soon!"

So why not go together? Mayer is embarking on his own world tour from April to June. But the singer/guitarist also didn’t accompany Perry on her trip to London and Milan. When Perry returned to Los Angeles, he remained in New York.

The two have had a tumultuous relationship and are known as “the” on-again, off-again couple. However, things seemed like they were becoming more serious after the celebs collaborated on the song “Who You Love,” off of Mayer’s latest album, “Paradise Valley.”

But there's still hope that this is all one big nasty rumor and that Perry and Mayer are just as in love as ever. She was spotted wearing a huge diamond ring at the Elle Style Awards last week in London.

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