Jennifer Aniston

After Brad Pitt left Jennifer Aniston for Angelina Jolie, Aniston developed an irrational fear that every man she dates will leave her for another woman. Which is why Jennifer Aniston had Kimberly Stewart kicked out of a John Mayer concert. Kim and John know each other from clubbing in LA and apparently, Aniston felt threatened by that creepy monster.

“Kim was pulled off the stage and escorted through the Hard Rock VIP tent with a face like thunder, shouting: ‘Why doesn’t he want me here? Is this because of her?’ “She totally embarrassed herself, but Jen looked relieved.”

Other things that might threaten Aniston: Jessica Simpson, John Mayer’s niece, a puppy, a toaster and that 12-year-old John Mayer fan Jennifer punched out in a fit of jealous rage.