Around 2000, I met David Butcher, who was then head of Invesco’s corporate pension division. Although we were competing with him, it was immediately clear that David was a good guy and that losing to him still meant the client got a good deal.

Other people I knew, thought the same way, my partner Stella for one.

David left pensions about ten years ago to work in the voluntary sector. He cut the ties and moved on but Stella and I often talk of him, his love for Hendrix and good wine and the values he had- which for a time, set the tone and standards not just for Invesco but for us all.

Last week, his face appeared on my Linked In timeline, albeit marked by the intervening period. It was obvious that he’d been through some tough times but the face was still smiling, I got in touch and David sent me his story.

Most people have come across ME. It seems to strike hardest at those who work hardest and have given most. But until I read this, I had no idea of what it feels like to be afflicted in this way.

On 13th February 2012, I collapsed from exhaustion. I was bed bound for 6 weeks, sleeping 18 to 20 hours every day. I was so exhausted that it was all I could do to crawl to the bathroom.

This was no ordinary exhaustion. It was exhaustion unrelieved by sleep. No matter how long I slept I woke up feeling just as exhausted. The slightest exertion such as brushing my teeth left me completely depleted. A shave and shower were out of the question.

After 6 weeks I was able to get up for about an hour every day. But now my nervous system was so ‘wired’ that I couldn’t sleep. The insomnia lasted 3 months and even with sleeping pills I  couldn’t sleep more than 2 or 3 hours a night.

I became desperate about this mystery illness. Despite my limited energy, I started researching ‘exhaustion’ and discovered ‘myalgic encephalomyelitis’  and ‘chronic fatigue syndrome’ (ME/CFS).  My immediate reaction was denial. Then slowly I started to accept I probably had ME/CFS. I felt lost, scared and vulnerable.

I went to see my GP. In fact, I saw 8 different GPs at my local practice and all to no avail. They could tell me nothing about the causes of ME/CFS and even less about how to treat it.

This led to depression. All the doctors said it was depression that was causing the fatigue and prescribed me anti depressants. I suggested that my depression was natural given how desperate I was to understand my illness, how isolated and lonely I felt. I was convinced that the depression was not the cause of ME/CFS. I thought it was a consequence. But this all fell on deaf ears.

My doctor advised me that I could not be given a diagnosis for ME/CFS until I had suffered from it for 6 months. I remember saying to her “so what you’re telling me is that I have to be ill with ME/CFS for 6 months before you can confirm my diagnosis, and then you still have no treatments to offer me?”

Don’t get me wrong, I think that the NHS, its doctors and nurses are absolutely marvellous but the reality is that they are behind the curve when it comes to ME/CFS . And this is a serious and complex illness.

Then I discovered that my friend’s mother had been suffering from ME/CFS for 25 years. She recommended me to a functional medicine specialist. Functional medicine looks holistically at the functioning of every system in the body and how they interact together. It looks at causes not symptoms.

The functional tests revealed that I had a serious malfunction of the adrenal glands, the thyroid gland, the digestive system and the mitochondria (the energy producing factories in our cells). These malfunctions were the cause of my loss of energy. Here was the proof that ME/CFS was a physical illness.

So what caused these malfunctions? Stress played a huge part. Many years of cumulative stress in demanding roles in the City combined with the frustration of corporate politics had taken their toll. But it was me too: I have an achiever type personality profile, always pushing myself relentlessly onwards. In 2005, my then employer decided to get out of the business of which I was CEO. I was surplus to requirements and already too old to find another suitable position. It made me wonder what on earth the previous 5 years were for?

In May 2006, my wife was diagnosed with breast cancer. I immediately became her carer 24/7. Because of my ‘achiever’ personality, I pushed myself to do my best for my wife and daughter, then aged 9. As usual, I ignored my own needs. I stopped exercising, resorted to comfort food and drank far too much.

At this time my father, who had been diagnosed with Parkinson”s Disease in 2002, started to deteriorate significantly. So between 2006 and 2010 my stress levels were off the scale. I had no job. My father was dying. My sense was that my wife was going to die too. In the summer of 2010 they both passed away within a few weeks of each other.

The combination of the cumulative stress of my work and the emotional trauma of losing my wife and father had seriously compromised my immune system. In 2011, I caught a series of bacterial infections. The consequent overuse of antibiotics combined with a flu vaccination were the straws that broke the camel’s back. With hindsight, my illness had been inevitable. Stress, emotional trauma and infections were the perfect storm for ME/CFS.

And my situation became worse before it got better. In 2013, I lost 20 kilos and my doctor feared that cancer could be the cause of weight loss. So I had to endure a colonoscopy, a gastroscopy and a video capsule endoscopy. This was my darkest time. I was close to the edge. Mercifully, I was given the all clear.

So what was my recovery strategy? In simple terms, it was giving my body the tools it needed to heal itself. This involved a focus on sleep (eventually), quality rest, discovering slowness, pacing myself and learning how to relax. Identifying the causes of my chronic illness through functional medicine testing was absolutely essential. Following a ‘stone age’ diet and taking the appropriate natural supplements to support the adrenals, thyroid, mitochondria and digestive system were fundamentally important.

I also realised that I had to focus on my head and not just my body because ME/CFS is an interaction between multiple systems both physical and psychological. I had to believe I could control my recovery. I had to learn to listen to my body. I had to be my own medical detective. I had to do a lot of trial and error with diet and natural supplements. I had to be patient, determined and focussed.

My daughter Charlotte then discovered The Optimum Health Clinic who specialise in helping ME/CFS sufferers. They have the unique advantage that most of their practitioners, including their founder, have suffered  from ME/CFS and fully recovered from it. They were terrific in showing me how to manage my thoughts and control my anxiety, both essential in reducing the fatigue. Their sharing the lessons of their recovery stories was incredibly valuable. Many hundreds of hours of yoga and meditation have also been extraordinarily important.

Now well on the way to recovery, I am able to work part time. Having recently been appointed Chairman of The Optimum Health Clinic Foundation, I am using my knowledge and experience to help other ME/CFS sufferers recover from this greatly misunderstood and under diagnosed illness.

The truth is that this illness has been a wonderful gift. My encounter with ME/CFS has been an encounter with me. It has enabled me to not just change a few behaviours but to achieve a profound change in terms of how I relate to myself and the world. The last 8 years have been hell, but without that pain and suffering I would not have achieved this inner transformation.

David Butcher