Matthew Perry & Julia Roberts
In his memoir Friends, Lovers and the Big Terrible Thing, Perry opened up about his two-month '90s romance with the Oscar winner, which began after Roberts agreed to guest star on Friends under one condition.
Perry wrote that the Pretty Woman actress "would only do the show if she could be in my story line," adding that he "had to woo her." To do so, he sent Roberts three dozen roses and a note that read, "The only thing more exciting than the prospect of you doing the show is that I finally have an excuse to send you flowers."
But their romance was ultimately shortlived because "dating Julia Roberts had been too much for me," Perry admitted. "I had been constantly certain that she was going to break up with me. Why would she not? I was not enough; I could never be enough; I was broken, bent, unlovable. So instead of facing the inevitable agony of losing her, I broke up with the beautiful and brilliant Julia Roberts."
Alanis Morissette & Ryan Reynolds
We have Drew Barrymore's 2002 birthday bash to thank for this unlikely celeb pairing. The Canadian stars even got engaged two years later, but called it quits in early 2007.
Milo Ventimiglia & Alexis Bledel
During their Gilmore Girls days, the co-stars struck up an offscreen romance between 2002-2006. The pair even discussed marriage at one point, with Bledel telling People, "I think everybody who has been dating for more than a couple of years probably talks about it at some point. It's a fun thing for us to talk about, but that's it."
Michael Bublé & Emily Blunt
The Devil Wears Prada alum dated the pop singer for three years up until 2008. Seven years later, Bublé denied rumors that a cheating scandal was to blame for their split.
Kim Kardashian & Nick Cannon
The E! reality star dated the rapper for a brief period of time in 2006.
Ellen DeGeneres & Anne Heche
Their 2000 split caused major tabloid controversy, with Heche going on to marry Coleman Laffoon one year later.
Jessica Biel & Chris Evans
Young love at its finest! The then-rising stars dated from 2001-2006.
Scarlett Johansson & Jack Antonoff
The Bleachers singer romanced the Black Widow actress during their high school days, even attending prom together.
Kate Hudson & Alex Rodriguez
The New York Yankees star had the A-lister cheering him on from the stands for several months in 2008.
Reese Witherspoon & Jake Gyllenhaal
The A-listers struck up a two-year relationship after working together on the 2007 drama Rendition.
Sarah Jessica Parker & Robert Downey Jr.
The Iron Man star's substance abuse issues plagued much of their highly-publicized relationship, which spanned 1984-1991.
Zachary Quinto & Jonathan Groff
Quinto and Groff dated a few years before they broke up in mid-2013, but remain friendly to this day.
Jennifer Garner & Scott Foley
After meeting on set of Felicity, the actors tied the knot in 2000. Three years later, they separated.
Sandra Bullock & Matthew McConaughey
These two became the subject of romance rumors after co-starring in A Time to Kill, which ultimately turned into a two-year relationship.
Asked by Cosmopolitan in 2003 how they managed to stay friends, Bullock said, "It's the work we both put in. There's a great amount of respect and love. I feel very cared for by Matthew. No matter where he is in his life or where I am in mine—he could be married—I know we would stay close."
Tom Cruise & Penelope Cruz
2001's Vanilla Sky brought the A-listers together for a three-year relationship. Cruz's rep denied that Scientology played a role in the breakup, saying that the actress, while not a Scientologist, had found the church courses she took "beneficial."