Katy Perry broke up with John Mayer because he kept breaking promises.
The 'Teenage Dream' singer had an on/off relationship with the guitar player from 2012, but they decided to finally split last month, blaming her upcoming Prismatic tour, although a source claims there was more to it than conflicting schedules.
The insider told HollywoodLife.com: "The last time they broke up John won her back by making a ton of promises. He was going to put her first, but now he's falling back into his old patterns.
"Like, he shuts off his phone and disappears all day and night - he says it's because he needs alone time, but it's sketchy for sure."
Katy, 29, was left heartbroken when her marriage to Russell Brand ended after 14 months in December 2011, and is now not prepared to deal with difficult behaviour from the man in her life.
The source added: "Katy isn't willing to put up with any shenanigans. She's devastated but she felt she had to do this to take care of herself."
The duo released a romantic duet 'Who You Love' last December and looked cosy on Valentine's day when Katy was spotted with a ring on her wedding finger, but only weeks later they parted, although one friend thinks they could get back together in the future.
They said: "Not sure how long it will last this time but yes, it is off for now."