In the year 2000, these ten celebrities were all in very different places. Breakups, breakthroughs, meltdowns, and comebacks have all taken place since Y2K, and we've been there to witness it. Ahead, a star-studded trip through the past ten years.

What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

1. Jennifer Aniston/2. Brad Pitt, Y2K: When this picture was taken in February of 2000, Pitt and Aniston had been dating for roughly two years. Just a few months later, the two were married, a union that lasted until 2005, when the couple split and Pitt moved on to Angelina Jolie. The story was a tabloid dream come true, with lurid tales of Pitt, Jolie, and Aniston creating a soap opera storyline that's still being played out, nearly 5 years later: just this week, Star Magazine ran a cover declaring that Jennifer Aniston was finally ready for baby..."with Brad's help!"


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

3. Angelina Jolie, Y2K: But the Brangelina storm hadn't swept through Jolie's life in 2000; at that point, she was married to Billy Bob Thornton, and delighting/horrifying the press with tales of their torrid love affair. Jolie claimed that she wore a vial of Thornton's blood around her neck, and the two weren't shy about discussing their sex life on the red carpet. By 2002, Jolie had adopted her first child, Maddox, and by 2003, Thornton and Jolie had divorced.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

Jennifer Aniston, 2009: Aniston has spent the better part of the decade living in the tabloids; after Friends went off the air in 2004, she segued into a movie career, though the public seemed more interested in the scandal surrounding her divorce from Pitt. She has been painted as "lonely" and "desperate" by many a tabloid magazine, even though she's dated several famous men, including John Mayer and Vince Vaughn. Though the Brangelaniston blitz shows no signs of slowing, Aniston continues to make films and most likely hopes that the world moves past her 5-year-old divorce as we enter a new decade.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

Brad Pitt & Angelina Jolie, 2009: Jolie and Pitt, arguably the world's most famous couple, have gone on to have three biological children together; Pitt has also adopted Jolie's adopted children, and all of their children share the surname "Jolie-Pitt." The couple have devoted much of their energy to charity work through their Jolie/Pitt Foundation. and, like Aniston, I assume, to trying to break out of the Brangelina media blitz. Jolie, who 10 years ago spent time discussing the vials of blood around her neck, has since become a UN Goodwill Ambassador and is well-known for her humanitarian efforts.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

4. Britney Spears, Y2K: Britney was on top of the world in 2000, riding the success of her second album, Oops...I Did It Again. In 2001, she performed her now-infamous "I'm A Slave 4U" dance at the MTV Video Music Awards, snake, see-thru bodysuit, and all, but things started to come off the rails in 2002, when her relationship with Justin Timberlake came to an end. Timberlake's solo career skyrocketed with songs about how Britney did him wrong, and Spears' career, and carefully marketed sexy virgin image, began to crumble.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

In 2004, Spears married Kevin Federline (it was technically her first marriage, after an ill-advised 24 hour marriage to a childhood friend in Vegas). The marriage would produce two sons for Spears, Sean Preston and Jayden James, but it would also produce a number of disturbing problems.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

By 2008, Spears and Federline had divorced, and Spears' erratic behavior had cost her custody of her two children. She spent most of her time in court or driving around Los Angeles, wearing wigs and stopping at gas stations and Starbucks shops. Spears' behavior become increasingly bizarre, with the pop star shaving her head on camera and giving a disastrous performance at the 2007 MTV Video Music Awards. After she was hospitalized twice for psychiatric reasons, her father, Jamie Spears, won the right to a conservatorship over his daughter. Spears' career and personal life were then intensely monitored and controlled by her father.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

Britney Spears, 2009: By 2009, Spears' personal life and career appear to be back on track; she embarked on a world tour behind her successful record, Circus, has extended visitation rights with her children, and her conservatorship may end soon, leaving her in control of her own destiny for the first time in years. Hopefully, the next decade will be a little easier for Britney than the last one was.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

5. Beyonce Knowles, Y2K: Beyonce, circa Y2K, was still with her group, Destiny's Child, figure skating across America, recording hits like "Independent Woman, Part 1" for the Charlie's Angels soundtrack. After several successful Destiny's Child singles like "Bootylicious," (which she co-wrote) Beyonce decided that we were, in fact, ready for this jelly, and decided to strike out on her own with her 2003 album, "Dangerously In Love." Destiny's Child split in 2005, and Knowles' solo career has been going strong ever since.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

Beyonce Knowles, 2009: By 2009, Knowles had established a wildly successful solo career, introduced the world to her alter-ego, Sasha Fierce, married long-time boyfriend Jay-Z in a private ceremony, and branched out into acting with roles in Dreamgirls and Cadillac Records. Her video for "Single Ladies" is perhaps one of the most memorable videos of 2009, if not the entire decade.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

6. Tom Cruise & 7. Nicole Kidman, Y2K:Though it seems a bit hard to picture at this point, Tom Cruise and Nicole Kidman started the decade as a married couple; in 2001, they'd split after 11 years of marriage.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

Nicole Kidman, 2009: Kidman's career skyrocketed after her divorce from Cruise; in 2003, she received the Academy Award for Best Actress for her portrayal of Virginia Woolf in The Hours. Kidman went on to marry country music star Keith Urban in 2006, and in 2008 the couple had a daughter together named Sunday Rose.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

Tom Cruise, 2009: Tom Cruise's career hasn't fared as well as his ex-wife's this decade. His career tanked following an incredibly weird series of television appearance, such as a Today show appearance wherein he called Matt Lauer "glib" and accused him of not understanding the history of psychiatry like Cruise did, as well a now-infamous appearance on the Oprah Winfrey show during which Cruise jumped on Oprah's couch to declare his love for actress Katie Holmes, whom he married in 2006. The couple's marriage that year, as well as the birth of their daughter, Suri, has made them a tabloid favorite ever since, with Tom's association with Scientology often overshadowing both of their acting careers.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

8. Whitney Houston, Y2K: Whitney started the decade with a Grammy Award for Best R&B Female Vocal Performance, but her career faltered as the decade went on. Accusations of drug use ("crack is wack") swirled around her marriage, which was documented for a depressing reality show called Being Bobby Brown, which showed a side of Houston the public had never seen before (and gave The Soup one of its favorite catchphrases). Houston divorced Brown in 2006, went to rehab for what she now admits was drug addiction, and began to get her career together.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

Whitney Houston, 2009: In 2009, Houston returned with her album, I Look To You, discussed the difficulties of the past decade in a tell-all interview with Oprah and received a standing ovation at the American Music Awards following a performance of "I Didn't Know My Own Strength."


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

9. Lindsay Lohan, Y2K:, Lohan, shown here in 2001, began the decade under the Disney umbrella, starring in films like Freaky Friday and Confessions of a Teenage Drama Queen. Her breakthrough came with 2004's Mean Girls and the release of her first album, Speak, though troubles in her personal life soon seemed to follow, with the actress being accused of having everything from an eating disorder to self-harming issues to drug addiction.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

Lindsay Lohan, 2009: It has not been a great second half of the decade for Lohan; her last few years in the press have been dominated family troubles, her on again-off again relationship with Samantha Ronson, rumors of violent and erratic behavior, and film duds like I Know Who Killed Me and the straight-to-television Labor Pains. Yet Hollywood loves a comeback story, so we'll have to see what the next decade has in store for Lilo.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

10. Joaquin Phoenix, Y2K: Phoenix started the decade by scoring an Academy Award nomination for his performance in Gladiator; a second nomination would come in 2005 for his portrayal of Johnny Cash in Walk The Line. In 2008, he shifted gears and began focusing on his rap career, which confused pretty much everyone.


What A Difference A Decade Makes: 10 Years In The Lives Of 10 Celebrities

Joaquin Phoenix, 2009: By 2009, Phoenix claimed he was retiring from acting to work on his rap career full-time. He discussed his plans during a now-infamous appearance on the Late Show with David Letterman, appearing completely out-of-it and nearly unrecognizable behind shades and a grizzled beard. Phoenix claims his rap career is "not a joke," and his transformation from actor to rapper is being filmed for an upcoming documentary by his brother-in-law, Casey Affleck. Whether or not Phoenix's career change will be successful (or if it's all an elaborate hoax) is yet to be seen, but I suppose all will be revealed at some point during the next decade. After all, you never know what can happen in just 10 years.