Sadly, Jennifer Aniston may be setting herself up for another heartbreak, IN TOUCH WEEKLY reports.

JOHN MAYER HITS ON ANOTHER WOMAN

Just two days before she flew to Amsterdam to meet John, the 30-year-old rock star was in a coffeehouse in the Dutch city, trying to convince a pretty tourist to have dinner — or after-dinner drinks — with him. On June 20, John approached Chaton Anderson, a writer from Manhattan Beach, Calif., and sat beside her at her table. “I think he thought I was from Amsterdam, because he said, ‘I am John and I am a singer,’ ” Chaton tells In Touch exclusively. “I laughed because I knew who he was.” Chaton, 32, also was aware that he has been dating Jen. “I asked him what his relationship status was,” she explains. “He said, ‘It’s vague.’ I asked him what that meant and he said, ‘You know, it’s very vague.’ I just laughed. I never mentioned Jennifer and neither did he.” Chaton gave John the number of her prepaid cell phone — but the phone was later stolen. “I’ll never know if he called or not,” she says. What she did say is that John was acting very much like a single man. “I never would have guessed he had a girlfriend at all,” Chaton adds.

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