Michelle Williams channels Marilyn Monroe look, talks Heath Ledger

(CBS/AP) - Actress Michelle Williams, who is channeling Marilyn Monroe in her latest movie, tells Vogue magazine that the death of former fiance Heath Ledger has affected all facets of her life.

The 31-year-old actress and mother says in the magazine's October issue that experiencing loss has changed her daily interactions, her career and how she acts as a parent and friend.

Pictures: Michelle Williams
Pictures: Heath Ledger

She says she now looks at life from a "lens" where everything is "impermanent."

The father of Wiilliams' child, Ledger was 28 when he died in January of 2008 after an accidental overdose of prescription drugs.

Williams, a two-time Oscar nominee, may be able to use some of her experiences as she plays Marilyn Monroe, another Hollywood star whose life was cut short, in her new film, "My Week with Marilyn."

Directed by Simon Curtis, it's about a week of Monroe's life in 1956 while filming the movie "The Prince and the Showgirl." The biopic, which opens in November, also stars Eddie Redmayne, Judi Dench, Emma Watson and Keneth Branagh.

The Montana-born Williams says she tried to gain weight for the role to have some of Monroe's famous curves but it all went to her face. She opted instead to fill herself out with padding.

Williams says channeling Monroe made her feel "like being reborn."

The October issue of Vogue hits newsstands on Sept. 20.