Katy's most high-profile postdivorce relationship was with singer John Mayer; the two began dating in June 2012 but were rumored to have split later that Summer. They were back on by October, spent the holidays together, and attended the Grammys as a couple before calling things off a second time in March 2013. Three months later they were back on and recorded a duet, "Who You Love," for John's Paradise Valley album. It was smooth sailing for Katy and John until February 2014, when they called it quits again as Katy was preparing to go on her Prismatic world tour. A source close to the couple said at the time, "I can't keep track anymore. But for now, they are done." A few more meet-ups between the two sparked rumors of a reconciliation, but they were never confirmed.
