Michelle Williams said her life has "kind of repaired itself" since the death of her former fiancé, Heath Ledger, and that his passing has affected all facets of her life.
"It's changed how I see the world and how I interact on a daily basis. It's changed the parent I am. It's changed the friend I am," Williams said in the October issue of Vogue magazine. "It's changed the kind of work that I really want to do. It's become the lens through which I see life-that it's all impermanent."
Ledger was found dead in his New York apartment in 2008, months after he and Williams broke up after a three-year relationship. He died from an accidental overdose of prescription medication.
Williams and Ledger starred together in the 2005 movie "Brokeback Mountain", which earned Williams an Oscar nomination. They have a 5-year-old daughter named Matilda.
In the Vogue issue set to be on newsstands September 20, the 31-year-old actress also talked about her portrayal of Marilyn Monroe in the upcoming film, "My Week with Marilyn."
The film is based on the week that British writer Colin Clark worked as Monroe's assistant while she was filming "The Prince and the Showgirl" in the United Kingdom in the summer of 1956.
Williams said she prepared for the role by spending six months reading and watching everything about Monroe, who died in 1962 at age 36.
Monroe remains one of Hollywood's most iconic sex symbols. Williams said she tried to gain weight to have some of Monroe's curves, but it all went to her face. She decided to just fill out with foam padding.
"My Week with Marilyn" will premiere at the New York Film Festival on October 9 and be released in theaters on November 4.
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