Image copyright Getty Images

In 2011, girl group The Saturdays were filming a music video in Iceland for their single My Heart Takes Over.

But one of the members - Frankie Bridge - just didn't want to do it.

"I'd reached a point where I couldn't cope with everyday life," she tells Radio 1 Newsbeat.

After years of poor mental health, that was the point when those closest to Frankie decided she needed to go into a specialist mental health hospital.

"I was constantly crying and telling my partner [footballer Wayne Bridge] that I didn't really want to be here anymore."

The video shoot would last two days and was already paid for, so Frankie and her manager decided she'd keep working and be admitted when it was over.

"Luckily it was a moody shoot so I didn't have to put on this happy, smiley front," she says.

'I'm sharing my story to tell people they're not alone'

On her return to the UK she went into hospital where she was "terrified but relieved".

"It was a sense of relief that I could hand my life over to someone else. I was no longer my own responsibility. It was the hospital's responsibility to keep me alive and make me better."

For years, Frankie has chatted openly about her mental health issues and the way she has coped - and struggled - with things like depression, anxiety and suicidal thoughts.

She's now written a book, Open: Why Asking for Help Can Save Your Life, because she's "proud" to have come out the other side and be happy.

"I still suffer with depression and anxiety but I just know how to deal with it better now.

"It's not a self-help book," she says. "I'm sharing my story to tell people they're not alone."

Image copyright Getty Images Image caption Frankie had a panic attack before a performance with The Saturdays because she felt "overwhelmed"

During her time in The Saturdays, she says her bandmates - Rochelle, Vanessa, Mollie and Una - didn't know the extent of her health problems until they saw her have a panic attack.

"It frightened them and they were shocked at how bad it was because up to that point I was so good at hiding it."

'I felt I looked really sad'

She also remembers her first live TV appearance after coming out of the psychiatric hospital.

It was on the BBC's Children In Need and for anyone watching it went without a hitch - but when she sees the performance on YouTube now she laughs and says how she was "faking it".

Frankie's life in the band meant she was used to getting ready with loads of people around her and being in a manic changing room.

However, coming out of hospital and going back into that environment was "too intense".

"I had a panic attack in the toilets because I was so overwhelmed. I felt I looked really sad."

Image copyright Getty Images Image caption Frankie was supported by her now-husband Wayne Bridge, but says he could have "easily walked away"

One of the constants in Frankie's life has been her husband, ex-footballer Wayne Bridge, who she's been with for a decade.

"At the time, I didn't think how much it was affecting him and now I feel awful.

"We'd only been together a year and he's got this new girlfriend and he's having to take her into a psychiatric hospital. He could have easily walked away then."

'It can't be fixed'

Frankie says Wayne struggled too but he took the time to try to understand what she was going through.

"My doctors had sessions with him to explain what was happening and why I was feeling a certain way."

She says she tells Wayne to try to not "fix her".

"All I need is for you to listen to me because it can't be fixed," she says.

"Just be there, embrace it and let them know they're not alone."

Image copyright Getty Images Image caption The Saturdays had 13 UK Top Ten singles between 2008 and 2013

Frankie and Wayne have two young children - Parker and Carter - but pregnancy was also tough for Frankie to balance with her depression.

"It was weird because one of the reasons I wanted to get better was because I wanted to have children and I wanted to be a young mum," she says.

"When I got pregnant I had no control over my body. I had water retention, I had morning sickness and I put on a lot of weight really quickly."

Frankie had also had an eating disorder, and says it was hard to accept the changes to her body, which was made worse by people online commenting on her appearance.

"It fed into every insecurity that I had. My body had been my armour and I no longer had that anymore."

Image copyright Comic Relief Image caption Next for Frankie? She's taking part in a new Sport Relief challenge

Now she's preparing for Sport Relief's latest celebrity challenge, On Thin Ice - and it's for a cause that's close to her heart.

"I'm really nervous because I've had no time to train. It's all in aid of mental health I couldn't say no," she says.

Frankie and other celebrities (including Radio 1's Nick Grimshaw) will trek 100 miles across a frozen lake in Mongolia.

"It's all about ticking off those things that I'm anxious about going into situations that make me uncomfortable to prove to my anxieties that they're wrong."

Visit the Radio 1 Advice Pages for more information about mental health issues.

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