She started the decade as Rachel Green on Friends and Mrs. Brad Pitt
in real life. By the end of the decade, our favorite girl next door had blossomed into a full-blown movie star—and the world's most famous single lady, her love life a national obsession (when we weren't obsessing over her insanely yoga-toned bod). And yet, through all the ups, downs and John Mayers of the past 10 years, Aniston, 40, has always flaunted optimism. "You just have to love your life," she told PEOPLE last year. "I have my health; I have my friends; I have my loved ones. I'm extremely lucky."