'I look back and I can't believe the strength he had': Catherine Zeta Jones opens up about her husband's battle with cancer, and her own wrestle with bipolar disorder

She has endured a turbulent few years as she battled bipolar disorder following her husband's cancer diagnosis in 2010.

But Catherine Zeta-Jones reveals she has created a safe haven in her home where she can hide away.

'We spend a hell of a lot of time together, so we are careful to maintain our space,' says the 43-year-old actress.

'We recently had an extension built, to house a closet. It's like the Tardis - I go in there and never come out.'

Catherine was in rehab for most of May after voluntarily checking herself in to get treatment for her bipolar disorder.

'Bipolar is something I have been dealing with for a long time,' she says, speaking with the Sunday Telegraph's Stella magazine.

The Welsh star of Cabaret and Red 2 says when she got 'sideswept ' by Douglas' illness it was a trigger for her balance to go a bit off. 

'Not sleeping, worry, stress' are just some of the symptoms she recalls suffering.

'I wasn't as strong as I thought I could have been,' she confesses of the time he was receiving chemotherapy. 'I look back and I can't believe the strength he had.'

After a successful stint in an undisclosed health care facility in May, Catherine Zeta-Jones slowly got back into her everyday life.

She was pictured returning to her New York apartment after the school run, just one day after her exit from rehab. Douglas, 68, later said his wife was doing 'wonderful.'

She last visited a similar facility for five days in 2011 in a bid to better manage her disorder and sort out the medication that she was taking

Michael Douglas and Catherine Zeta-Jones hold hands at an event in New York City in April

n an interview with Metro last month, Douglas reflected on his wife's troubling disorder.

'Sometimes you don't think you need any meds at all, and you forget your meds. Then all of a sudden, you get on a real ride.'

The doting husband insisted that the actress doing well: 'But she's fine. She's got it stabled out. She's doing great and I can't wait to see her,' he said.

The Behind The Candelabra actor admitted that the mental health condition is unpredictable and can creep up on you at any time, saying: 'It's a slippery slope, this bipolar stuff.'

Catherine Zeta-Jones pictured in May just after leaving rehab for treatment for bipolar disorder