Andrea McLean says 'SAS: Who Dares Wins' brought back memories of an abusive relationship and sparked her emotional breakdown.
The 50-year-old star was left feeling suicidal during a difficult period which came after an incident two years ago on Ant Middleton's gruelling reality show when she was marched with a bag over her head.
Reflecting on the moment the cover was taken off to reveal an instructor, she told Closer magazine: "I'd put everything I'd experienced in a box, but suddenly it was like I was back there.
"Instead of seeing an instructor's face, I was seeing another person's face. He seemed to hate my soul and really specific events went bang in my head.
"I've had people say terrible things to me in the past. I've been told I am worthless, stupid, talentless and ugly, and if someone drip-feeds that into your consciousness, the plucky girl you once were completely disappears."
The 'Loose Women' star was left "anxious and overwhelmed" and "got into a spiral of negativity" despite the support of her husband Nick.
Looking back to last year's National Television Awards, which came in the midst of her breakdown, she added: "The NTAs are such a joy, but that year I could barely face the noise or laughter.
"I cried all the way to my hotel, where I'd booked a room to get ready, then I did a few photos on the red carpet before walking away.
"Afterwards, I sobbed all the way home. I felt like I was short-circuiting."
Andrea - who has opened up about her experiences in new book 'This Girl Is On Fire' - underwent CBT (cognitive behavioural therapy) and talking therapy to help her overcome her issues.
She said: "Two years ago, I thought I'd never feel happy again but, now, whenever something lovely happens, I thank myself for keeping going."
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