Michelle Williams

Ten months after the death of ex-fiancé Heath Ledger, Michelle Williams says time has only worsened her grief.

"It's so sad," Williams told Newsweek of Ledger's accidental overdose, adding that her pain is "always changing."

"What else can I say? I just wake up each day in a slightly different place — grief is like a moving river, so that's what I mean by 'it's always changing,'" she said. "It's a strange thing to say because I'm at heart an optimistic person, but I would say in some ways it just gets worse. It's just that the more time that passes, the more you miss someone. In some ways it gets worse. That's what I would say."

Williams and Ledger split in September 2007 after three years together. Ledger was found dead in his apartment four months later. The couple's daughter, Matilda, is 3.

After continuing to work following the death, the actress, whose next film, the indie drama Wendy & Lucy, opens Dec. 10, plans to take a year-long break to focus on motherhood.

"I don't want to work while she's in school," Williams said. "I want her to have a routine. I want the plainest, simplest, most ordinary, habituated routine possible. I just want to know what's coming next."