The 27-year-old tells Vogue magazine's October issue, there was a time when she wasn't in such a good place.
She recalls a time when the fame from such roles as "Bend it like Beckham" and the "Pirates of the Caribbean" franchise was too intense. She says she "literally had no life outside of acting" and desired to "not be 'on' all the time."
Instead of working, Knightley read books, cooked and lived in France.
The October issue of Vogue goes on sale nationwide Sept. 25.
"Anna Karenina" opens in limited release on Nov. 16.