Despite retiring from bareknuckle boxing, Derek ‘Decca’ Heggie is still exposed to a mountain of pain. Now it comes via some of the messages that pour onto his Facebook fan page:

‘In a bad place myself at the moment, my mam died two weeks ago and a week before that I had to have my little dog put to sleep so life is a bit rough at the moment. x’.

The messages - two or three hundred a day, says Decca - are prompted by his Facebook videos about how he tackles the depression and anxiety which, several years ago, drove him to attempt suicide.

He put on a tie, fixed it around a beam in the house he was living in, and kicked away the chair he was standing on.

What was going through his mind? “Nothing... you don’t really think of anything. It’s an escape from the world. When you’re thinking of suicide you don’t think about anybody else’s feelings. You don’t think about what you’re going to leave behind. You become selfish. You don’t intend to be selfish. You’re just thinking ‘I won’t feel bad anymore.’”

The beam snapped. From a cloud of dust Decca seized this second chance, albeit with many potholes in the road to recovery.

Now the fighter has become a healer. But at times it feels as if he’s drowning in other people’s pain.

“When people see a guy like me - a big, tough fella - open up it kind of gives them permission to open up. Especially men. When they watch the videos and see me talking, they think ‘Decca’s talking about me.’ Because I’ve been on that level as well. I’ve been at rock bottom.

“I get hundreds of messages a day. I’m thinking ‘Woah, I can’t handle this!’ I’m not a doctor. I can only tell people what’s helped me.”

His Facebook page attracts plenty of light-hearted messages. There is also an alarming number from people saying they are thinking of ending it all.

Decca tries to fight these fires. In response to one message he wrote: ‘Yes it’s difficult and it takes everything we have to do it. But we have two choices. Sit around watching our life go by. Or get up and start the hard journey of dealing with our demons xx’.

He says: “I want to help people but it’s impossible to help everybody individually. If you try and help everybody, you can bring yourself down. I try to switch my emotions off or it could lead myself back into the dark.”

How to help others without being dragged down? Next month Decca, 35, will talk to staff at Sellafield about his struggles.

He hopes to do more corporate speaking, to reduce the stigma around mental illness while filling the hole left by his retirement from fighting. Acting and personal training are his other paths.

Friendly and chatty, Decca was not always so open about the turmoil in his head.

“When I didn’t speak about it, the depression and mental illness grew like a cancer. I was close to being sectioned. I just lost control of my mind.

“When you lose control of your mind you lose control of everything. You’re in a dark place. You have no feelings. No emotion. You’re just sitting there looking into a blank space. You could be sitting in a room of 100 people but, to your mind, nobody’s there.

“I went through five months of complete depression and anxiety. Anxiety comes from negative thoughts. Once you learn to turn that negative thought into a positive, you no longer have anxiety.

“When I overcame my depression and anxiety, I felt I want to help people by telling them my story. I have this urge to help people. I get a massive buzz from it.”

Much of the story takes place on Carlisle’s Harraby estate. Decca has spent most of his life here. His tale has been frequently grim. For much of his childhood he was bullied by a local gang who left him with deep emotional scars.

At 15 he beat the ringleader unconscious. There were many more fights, one of which left a tooth stuck in his knuckle.

Decca became a doorman, took steroids while weight training and became hooked on cocaine.

His drug use declined after his suicide attempt and he’s now been clean for years.

“People use the past as an excuse,” he says. “It can stay there forever if you allow it to. I like to learn from my past mistakes. My drug abuses and all that. Instead of sniffing drugs again and making a fool of myself, I try to help other people.”

Decca says his previous behaviour began to make more sense a year ago when he was diagnosed with bipolar disorder.

Formerly known as manic depression, the condition affects moods, which can swing from one extreme to another.

“I knew there was something wrong in my life. I just didn’t know what was going on until then. Being bipolar can make you do uncontrollable things in a stupid way.

“Before I got diagnosed I would put big bets on at the bookies and think ‘Why have I done that?’ I’d buy trainers I couldn’t afford and be left with nothing. I used to get angry for no reason. You’re always putting yourself down.

“I know what it is now. I’m not sitting there questioning it. I know that I’m not going to be normal. I accept it so it doesn’t get me down. My role is to try and be as normal as possible.”

Understanding his mind does not mean Decca can always control it.

“Depression can hit you even when you’re at your happiest. I was my happiest when I came off the set off The Corrupted [a crime thriller which Decca acted in last year]. Every day for three or four weeks I was with Timothy Spall, Hugh Bonneville, Noel Clarke, Sam Claflin.

“Then to come home to my everyday life from a massive high... I fell into depression. At the bottom the only way is up. At the top the only way is down. When you’re at the top you’re going to crash at some point. Now I never fully get to the top. I sit between the middle and the top.

“Usually I can tell when I’m going to have a bad day as soon as I wake up. It’s like a dark cloud hanging over me. I get straight out of bed and go for a run. I do something positive. If you lie in bed you overthink and it just becomes worse. It grows like a cancer.

“We’re never going to get rid of mental illness. So we have to learn to live with it. I have to live according to my mental health. Diet, exercise, mindset. Every step I take in life is to give me a positive mind so I don’t go back into darkness. Every day is a fight.”

Decca had a blip recently: his first in three months. “I overcame it within a day, which shows how far I’ve come. I feel strong. I understand what it’s like to be at rock bottom. It moulded me into a strong person.

“I used to put an act on in front of people. Pretend I was happy. Now that smile is real because I am happy.”

Decca was unbeaten in his 15 bareknuckle fights. He became British heavyweight champion and in 2016 won the coveted Guvnor title against Julius Francis, a former opponent of Mike Tyson.

Decca’s autobiography, Prizefighter, includes this eye-catching sentence: ‘To be honest, I don’t even like fighting.’

Now he confirms: “I hate drama, trouble, confrontation. If I’m fighting for money I’ll happily knock 100 bells out of someone. Outside of that... at the gym if there’s a confrontation I get nervous.

“I can fight, but I don’t want to. I always say mugs fight for free. Why am I going to have a fight on Botchergate and get six months when I can fight in the hay bales and get two or three thousand pounds?

“I’m not interested in violence. People think ‘Big lad, tattoos, bareknuckle fighter.’ When I got diagnosed bipolar I thought ‘Bipolar, bareknuckle fighter - people are going to think I’m a monster.’ I’m not. If people want to approach me in the street they can.”

Some approaches have been unwelcome, from people who saw Decca as a meal ticket or a passport to a darkly glamorous world. He is trying to put that behind him.

“I attract leeches,” he says. “I don’t trust people. I would rather be a lone wolf than have 100 fake friends around me.

“I’m single. But if the right woman comes along... I’m looking for someone with a good heart. I’m not really interested in fame. I’m trying to use that in a positive way to help others.”

Escaping his image and his past might prove difficult. Decca may yet return to fighting: he is open to any lucrative offers from the brutal sport of mixed martial arts. His acting career has so far involved hard man roles.

Everyone’s personality has parts which seem to contradict each other. In the colourful world of Decca Heggie, the contrasts are especially strong.

A bareknuckle boxing champion who spends time at Carlisle’s Uma Kadampa Meditation Centre.

A man whose search for mental health includes a wide range of solutions. Exercise. Ice baths... and something else.

Decca grins, leans forward on his settee, and says: “What does help you - taking your nana to bingo. I love a game of bingo.”

n To contact Decca Heggie about speaking engagements, email managementdecca@gmail.com