Sources reveal to In Touch that it was Katy Perry who ultimately broke things off with John Mayer, ending their relationship after nearly two years of dating! Why? Because of her own growing uncertainty about his ability to stay faithful.

“She always thinks John is either going to cheat or is cheating,” the source explains.

And her fears might not have been so far-fetched. Now, sources confirm exclusively to In Touch that John got cozy with 24-year-old spin instructor Lauren McHale last spring during a brief break with Katy.

Katy Perry Looks “Upset” At Dinner With Friends Just Days After Breakup

“He was acting single,” an insider explains to In Touch of John, who bought Lauren and her friend’s drinks after meeting them at a Venice, Calif., bar before heading to Lauren’s home to continue the party. The insider adds that though they were just supposed to be on a short break, John showed no signs of any communication with Katy at all. “He told her he thought she was good-looking and didn’t talk about Katy at all,” the insider tells In Touch. “At the end of the night, he kissed her.”

For Katy, her uncertainty was enough to call things off, says the first source. “She’d rather have kept dating, but he wanted to marry her. He pressured her. He gave her a ring and made the relationship more serious, which scared her because of his past.”

Check out In Touch’s own Noah Levy dishing on Katy and John’s break-up on The Gossip Table!

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