Presenter Kirsty Young said she 'lost her sense of self' due to her experiences with chronic pain.
The star departed as host of Desert Island Discs in 2018 because of her fibromyalgia and rheumatoid arthritis.
She took a four-year break from presenting and returned earlier this year.
Speaking about her pain on the Christmas Day episode of the BBC Radio 3 show, Kirsty told Lauren Laverne that it 'grinds you away'.
"You lose your personality, you lose your sense of humour, you lose your sense of self – there's all sorts of things that go with it. It's awful," the presenter explained.
Fibromyalgia is a condition that causes widespread pain and extreme fatigue and symptoms vary from person to person.
Meanwhile, rheumatoid arthritis symptoms include pain, swelling and stiffness in the joints.
Once she finally got a diagnosis, her doctor told her to work a lot less but she initially resisted.
"And he said, 'Well, part of getting better is, we can introduce all sorts of drugs, we can monitor you, but you have to reduce the stress in your life and you have to take this seriously. You can't just keep shovelling painkillers down your neck, which don't work anyway, and feel shocking'," she recounted the doctor's words.
It was a moment of 'reality and clarity' for her and she ended up crying in her car.
Kirsty previously spoke about her health in an interview with the Sunday Times Magazine in May.
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She revealed that her fibromyalgia left her struggling to perform everyday tasks like cooking and driving, describing the pain as feeling like she'd been hit "with a baseball bat".
Kirsty explained to the magazine: "It's like somebody had drugged me, like you’d taken a sleeping tablet at the wrong time in the day and you were completely losing it".
She said that quitting Desert Island Discs – which she hosted from 2006 until 2018 – was "clearly the only option" as she tried to manage the condition with her doctor.
Kirsty, who admitted that she felt depressed at one point, said that with the help of a specialist and a pared-down lifestyle she has since come off most of her medication.
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