Isabel, a professional and mother-of-two in Dublin, was nearing her 40th birthday when her health collapsed, turning her from a sleep-deprived, high-earning "superwoman" into a bed-ridden "mess" overnight - or so it seemed.
"One morning I woke up and couldn't start my day, getting the kids to school and so on. My entire body hurt - like I'd been run over by a lorry.
"I thought I must have flu so I rang in sick to work feeling really guilty, because I never took time off work, not even when my children were born. I'd had some difficulty with Irritable Bowel Syndrome because I'd go all day without eating, then when I ate, my colon would seize up.
"An alternative practitioner had told me I had candidiasis, but then my GP explained that this condition doesn't actually exist."
After a week in bed, Isabel felt worse. "I couldn't think straight. I remember looking in the mirror and not recognising myself. I wanted so badly to die, that it was only the thought of my children that kept me alive."
She ended up in hospital for a humiliating series of tests on her bowel, as well as a brain scan. When the tests all came back negative, she was referred to a psychiatrist. "I thought the world had ended. I had now gone officially 'mad'."
It would be a year before Isabel felt well enough to leave the house for a short walk and two years before she returned to work.
"I became afraid of everything. I avoided the phone, the TV news, my friends, I couldn't read or focus on anything. The slightest thing sent me into a panic. I had nightmares every time I fell asleep - even during the day. And I was in constant, physical pain. A friend thought I had Chronic Fatigue Syndrome."
Gradually, through therapy under the supervision of a psychiatrist, Isabel was able to make sense of her life. Her childhood had been a nightmare in many ways, but she had always told herself it was normal.
In the 10 years before her illness, she had married, had children, experienced a marriage break-up, had a car accident and then one of her children had become seriously ill. As a "coper," Isabel had dealt with it all until the day she couldn't get out of bed anymore.
Isabel has rearranged her life - at no small economic sacrifice - to be less stressful and more fulfilling. She enjoys her work and finds that she accomplishes more in less time.
"I listen to my body now, instead of dampening my feelings with painkillers or a half-bottle of wine. I do meditation and I've found a spiritual core that I didn't realise I had. I'm coping well now. I don't define myself by my work anymore."