Just 18 months ago, Faye Dempsey was your average 30-something who loved going out with friends and running to keep fit.
But she has since been struck down by a little-known illness that, on some days, can leave her "virtually bedridden".
Dempsey, 33, has been diagnosed with fibromyalgia, a long-term health condition that causes pain all over the body, as well as chronic fatigue syndrome. She now wants to raise awareness of the condition.
"I try to keep active by taking short walks and I've even tried swimming, but it's unbelievable how hard things are. I ache the whole time and I'm so sensitive to everything - noises feel like hot rods in my ears," she told the Liverpool Echo.
Dempsey knew something was wrong with her health when she began to experience severe pains in her legs in the summer of 2014.
At the time, she was in good health and would often run up to eight miles per day to keep fit.
But the pain wouldn't ease, even with strong painkillers, so her doctor sent her for tests at the hospital.
A blood test revealed she had a low white blood cell level and, after a year of further investigation, doctors ruled out cancer as well as autoimmune and viral conditions.
Eventually Dempsey was diagnosed with fibromyalgia and chronic fatigue syndrome.
According to the NHS, the exact cause of fibromyalgia is unknown, but it's thought to be related to abnormal levels of certain chemicals in the brain and changes in the way the central nervous system processes pain messages carried around the body.
As well as increased sensitivity to pain, people with fibromyalgia can also experience muscle stiffness, difficulty sleeping, problems with memory and concentration, headaches and irritable bowel syndrome (IBS).
Chronic fatigue syndrome, also known as ME, is characterised by a feeling of exhaustion that can't be helped with sleep.
The NHS says it's not known exactly what causes the condition but theories that have been suggested include: a viral or bacterial infection, problems with the immune system, an imbalance of hormones, psychiatric problems such as stress, and emotional trauma.
Dempsey said she's aware that there's stigma attached to chronic fatigue syndrome and many people think she is simply tired.
"Sometimes you can't lift your head off the pillow. I can have a full night's sleep but in the morning it's like my eyes are glued shut and I've not slept at all," she said.
The combination of the two conditions has forced Dempsey to give up her job as a manager, but she's determined to remain positive.
She said: "I am strong enough to campaign, to get the word out there and push for more help to be available, and I'm happy to do it because it gives me a purpose. I feel like I can do something good and all this isn't for nothing."
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