Michelle Williams on the Death of Former Beau Heath Ledger

December 22, 2010

Michelle Williams' love affair with Heath Ledger in 'Brokeback Mountain' became a real-life romance while shooting the movie and the actress spoke candidly about Heath's death on "Nightline."

"That was happy," Michelle said about making 'Brokeback Mountian' with Heath, the father of her child. Michelle gave birth to their daughter, Matilda, in 2005 and the couple separated two years later. In 2008 Heath died from a supposed accidental overdose on prescription medication.

Since then, Michelle has coped with Heath's death and kept busy. The "Dawson's Creek" star and Ryan Gosling deliver raw, emotional performances in their new romantic drama 'Blue Valentine,' in theaters December 29, and the couple become extremely coy when they're asked whether or not they're dating.

"She's like Brigitte Bardot meets Clint Eastwood," says Ryan. "She's like a cowboy -- a sexy cowboy, or something."

Asked point blank if they're an item, Ryan responds with a look like the cat that ate the canary: "Creatively, we are doing it. Creatively."

Asked if they ever dated, he responds, "No, we're professionals."

"He looks like he's lying, but he's not," says Michelle with a laugh.

"I always look like I'm lying," says Ryan. "I know. That's my face."

'Blue Valentine' follows a couple, Dean and Cindy, who are trying to save their marriage. During the course of one night, they are flooded with memories of their relationship, from their courtship to love lost in past and present moments in time.

Michelle and Ryan actually lived in the house that served as the set, and even decorated and bought groceries.

"I moved into the house for sort of normal work hours -- 9-5," says Michelle. "We were told to make memories, basically, and inhabit it as Dean and Cindy would."

The stars are also naked – literally -- for a lot of the movie, and Michelle explains, "I let myself be far more brave and confident and risk-taking in my work than I ever would be in my life."

Watch ET for more with Ryan Gosling and Michelle Williams in 'Blue Valentine.'

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