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By Kat Giantis
No one expected Katy Perry and John Mayer to go the distance, what with their repeated breakups and makeups over the course of their 18-month romance. But now that they've reportedly parted ways yet again, the weeklies are dutifully weighing in on what went wrong.
"They're two very strong-willed people," a source explains, somewhat vaguely, to People. "Despite caring about each other very much and wanting to make it work, they are, at their core, quite different."
One purported issue: Katy, 29, loves to socialize, while John, 36, is now more of a homebody.
"At times they seemed really happy together and in love, and other times he seemed like he just wanted to get away from all the parties and go home," says the insider, adding that Katy's busy tour schedule also played a role. "She's a smart girl. She knows no relationship can survive that kind of distance and strain, and she's not going to slow down now when she's at the top of her game."
The tabloids, meanwhile, offer some less than savory speculation about what did them in.
"She always thinks John is either going to cheat or is cheating," a snitch alleges to In Touch. "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."
Star, meanwhile, floats a couple of theories: Perry may have found out that Mayer cozied up to a spin instructor last May, when they were on another break, and/or he was "fed up" with how she kept sporting diamond sparklers on her ring finger to pump up engagement talk.
"That drove him away," contends a spy. "He wasn't ready."
Perhaps Katy should consider this a bullet dodged.
When asked during a recent interview on Sirius Radio why some women return to their exes, Mayer dropped this load of fried baloney: "It is a connection to the past, a reaction to fear of the unknown. They go back with a guy they don't like just because they know how to get to his bathroom in the dark."
Head, meet keyboard …
As for Perry, she sidestepped the boyfriend question while promoting her tour in Australia.
"All of my fans are my boyfriend," she enthused, before pointing to a nearby koala (because, hey, it's Australia) and announcing, "This is my boyfriend!"
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