New York, Oct 17
Former "Friends" star Jennifer Aniston has upset close friend Courtney Cox by reuniting with rocker John Mayer.
Tmz.com reports a source saying: "Jen's friends are just worried that she will again be hurt by John."
Some friends feel things between Aniston and Mayer will be all over by Christmas.
After her divorce from Brad Pitt in 2005, Aniston has been in an on-and-off relationship with the rocker. Pitt and Aniston were married for more than four years.