Catherine Zeta Jones, Michael Douglas

Catherine Zeta-Jones and Michael Douglas are "taking a break" after 13 years of marriage, People reports.

The couple, who married in 2000, have decided to spend some time apart but haven't taken steps toward a legal separation or divorce, a source tells People. According to the report, they haven't been photographed together since April, and Douglas, 68, has recently been spotted in Sardinia while Zeta-Jones, 43, remains in New York. 

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A source close to the couple blames Douglas' recent bout with cancer and Zeta-Jones' struggle with bipolar disorder. "The stress has taken a toll on their marriage," the source tells People.

Douglas and Zeta-Jones have two children together: Dylan, 13, and Carys, 10 

Are you surprised to hear that Douglas and Zeta-Jones are separated?