Jennifer Aniston declared she's Courtney Cox's best friend since the first day, when they met in 1990, on the set of their show, "Friends". Jennifer confessed she was shocked at first by Courtney's attitude, who appeared to be so opene and honest.

Aniston says: "From the first day we met, she just dragged me outside and started telling me about her relationships. She's the all-around friend and the ultimate loyalist.

You can tell a girl's girl from a mile away. Courteney's not standoffish, she's not threatened by women, and she doesn't have to throw her womanliness all over you to show you what kind of woman she is. She's comfortable, and that makes you feel comfortable", Jennifer added.

Meanwhile, it is reported that Jennifer fainted on the "Break Up" set, after complaining of nausea and severe headaches, just two weeks ago.

Jennifer was officially diagnosed with heatstroke, after she collapsed during the shooting in Chicago, Illinois.

It seems that all the fuzzing around ex-husband Brad Pitt and Angelina Jolie affected Jennifer more then she has expected to.

Apparently, Jennifer Aniston was crushed after she has seen the pictures from People magazine with Brad Pitt and Angelina Jolie acting like a loving family, according to Britain's Daily Star.

Jennifer "freaked out" when she heard that her ex-husband is going to have a child with Angelina, as well.