Catherine Zeta-Jones' maid of honour is concerned for her health.
The couple recently ended their relationship to try to repair their 17-year marriage and a close friend has admitted she is worried for the well-being of the actress, who suffers from bipolar II disorder.
TV presenter Anna Walker suggested the stress of their romance breaking down won't help Catherine, who previously struggled to cope when the actor was diagnosed with throat cancer in 2010 - which he beat.
She told the Mail on Sunday newspaper: "The next few weeks will be very tough and I'm very worried about her. This is a very traumatic time and her mental health could be adversely affected.
"I'm sure it's not been easy for her to cope with the stress of Michael's illness.
"She's just had another round of treatment for her bipolar and if she can keep that in check under all this stress it will be a miracle. Her mother Pat is with her at the moment, so I know she's in good hands. And nowadays there is very good medication that can help."
Anna added her close friend will be troubled by her marital problems because she holds very traditional views about the vows she took.
She said: "'It will have hit her very hard because she definitely believes marriage is for once in a lifetime.
'Catherine is very old-fashioned and never wanted to ever go through a divorce.
"Her parents, Pat and Dai, have been together for more than 50 years and are her role models. She wanted her marriage to be like theirs."
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