The Hollywood power couple have decided to spend some time apart, according to PEOPLE magazine.
Neither Michael, 68, or Catherine, 43, have filed for divorce or taken steps towards a legal separation, according to sources.
The silver screen pair, who tied the knot in New York in 2000, have endured a turbulent few years with Michael's cancer battle and Catherine's struggles with bipolar disorder.
Behind The Candelabra star Michael was diagnosed with throat cancer in 2010 while Welsh actress Catherine has suffered with bipolar II disorder for some time. She received treatment for the disorder earlier this summer.
"The stress has taken a toll on their marriage," a friend said.
They haven't been photographed together since April, attending events solo and holidaying separately with their children Dylan, 13, and ten-year-old Carys.
"They want the best for their kids, no matter what happens," a family friend revealed.
The couple reportedly decided to spend time apart soon after Michael came back from the Cannes Film Festival in May.