7. John Mayer
The relationship everyone loved to hate produced some actual good times as well as bad during 18 months of makeups and breakups. At least Perry can reflect on happier times with his "Who You Love," featuring Katy, and her own song "It Takes Two," on which Mayer plays guitar.
8. Robert Pattinson
Robert Pattinson has been linked to Katy Perry more times than we can count in the past year. Have they ever actually dated? Or hooked up? They've clearly hung out a bunch, but the hard evidence is elusive.
The latest reports surrounding Katy Perry's love life (besides those involving Pattinson) involve veteran producer Diplo.
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