04/05/2004 at 01:00 AM EDT
This wasn't the ending Ethan Hawke had in mind when he married Uma Thurman at Manhattan's Cathedral Church of St. John the Divine in 1998. Back then, "I was incredibly confident," he says. "I knew that most actors that marry each other break up, but I was confident that we could beat that."
Almost six years later, he and Thurman are separated, their kids Maya Ray, 5, and Levon Roan, 2, are splitting time between their parents—and Hawke, back onscreen in the new thriller Taking Lives
, is left to explain what went wrong. "I always felt like a marriage works best on, say, a farm, where you are together and everyone has real clear-cut roles," says the 33-year-old actor. "But you know, our whole marriage was time negotiation. You hear actors say, 'Oh, we rotate taking jobs,' but that means that someone is always away."
Until last year the arrangement seemed to be working fine for Hawke and Thurman. After taking time off while his wife shot Kill Bill
in '02, Hawke headed to Montreal to make Taking Lives
, in which he plays a police witness opposite FBI agent Angelina Jolie
—his first high-profile role since earning an Oscar nod for '01's Training Day
. Like that movie, Taking Lives
is a departure from the smaller, angstier films (such as '94's Reality Bites
) that had previously defined his career. "Ethan is all about taking risks," says pal Richard Linklater, who directed Hawke in the '95 romance Before Sunrise
and a sequel, Before Sunset
, due this summer. "He digs into everything with a passionate curiosity. The mind never stops working. The mouth often never stops working."
In the brainy, cool Thurman—whom he met when they costarred in '97's Gattaca
—Hawke seemed to find the perfect foil for his restless creative energy: In addition to writing two novels, he has directed a music video, a play and a feature film ('02's Chelsea Walls
). And yet, he says, "Two people who are used to being the star of their own settings—it's very difficult." Last summer, news broke that Hawke had romanced twentysomething Canadian Jenny Perzow while shooting Taking Lives
. When he returned to Manhattan, he moved out of his family's apartment. Hawke defends himself against implications that it's solely his fault: "It's not like there was one event that led to the demise of our relationship." For her part Thurman, 33, now dating hotelier André Balazs, 47, told In STYLE, "It's not fun, but...you have to look at things as an opportunity for growth."
In recent months Texas native Hawke, who earlier this year wrapped a Broadway run in Henry IV
, has been spotted out dancing at nightclubs and has been casually dating. "It's time to move on," says a friend, noting that lately, "he's joking, laughing, smiling more." Still, one thing remains constant: "He talks about his kids all the time." Often seen out in New York City with their dad, Maya and Levon were frequent visitors to the Taking Lives
set, along with Jolie's 2-year-old son Maddox. Says Jolie: "We all kept sane because we played with our kids at lunchtime."
Next up for Hawke: Assault on Precinct 13
, a remake of the 1976 cop thriller. As for his writing career, he says he may put his recent heartache on paper: "Probably, I'm sure. I've got to let enough time go by."
Michelle Tauber. Caroline Howard and Amy Longsdorf in New York City and Alicia Dennis in Austin