It started with a feeling of isolation, of not wanting to engage with the world. He didn't want to answer emails, and hundreds of answerphone messages went unreturned.
Feeling as though the world was against him he didn't want to leave home. Gripped by anxiety and a fear of impending doom there was a sense everything was about to fall apart and that he was powerless to do anything about it.
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Nonetheless, if his world was going to collapse, it was going to collapse on his own terms.
That was in late 2014, when former footballer Clarke Carlisle came very close to ending his life.
"How can I sit here in front of you and say that four years ago, I put myself in front of a 10-ton lorry, at 60 miles an hour and I didn't break a single bone in my body," Carlisle told CNN Sport at his home in Preston.
Carlisle had intentionally stepped out in front of a lorry on a road near York, just before Christmas. After several weeks in hospital, he managed to recover from the collision — remarkably unscathed. He describes his survival as a "miracle."
'Britain's brainiest footballer'
A former English Premier League footballer, Carlisle played for clubs including Preston, Burnley, Watford in a career spanning 17 years.
The 38-year-old was once dubbed "Britain's brainiest footballer," even appearing on the mentally bamboozling British game show "Countdown" -- he won, taking home the show's famous teapot trophy.
He says the suicide attempt in 2014 was a turning point for him, but his struggle with depression has persisted and about a year ago, in September 2017, he was reported missing, only to be discovered on the streets of Liverpool.
"I was intent on taking my own life," says Carlisle, who shatters the idea that footballers lead cushioned and painless lives, unperturbed by the challenges that affect everyday human beings.
"I was wandering around the streets of Liverpool, wondering what's the best place for me to die."
He was looking for the most practical way to die. How would he want his wife to find him? What about the first responders? And how would his suicide impact witnesses who found him?
"I was thinking about a responsible way to die. It was that procrastination that allowed a couple of passersby to intervene," he said.
After his return to safety, Lancashire police thanked members of the public for sharing a missing persons appeal.
It's that disappearance in 2017, which still haunts him.
"Now, a year down the line, where I am in the healthiest place I have been in my life -- I would say that is the one that troubles me the most, because it was at a point when I was most aware.
"It's at a point where I knew that I suffered from depression, it's at a point where I had established my own charity to help educate others, yet still the illness was able to take me to those depths again."
Clarke was diagnosed with depression in 2010. With the help of therapy he was able to pinpoint the inception of his depression to 2001, during a period in his career where he had picked up a bad knee injury.
Clarke said injuries were one of the "triggers" for the worsening mental health of footballers.
It's a view supported by a 2015 study organized by the World Players' Union FIFPro, which found that professional footballers who had sustained three or more severe injuries during their career were two to nearly four times more likely to report mental health problems than those who had not suffered from severe injuries.
As he looks back on his each of his suicide attempts, Carlisle says that they comprised a two-three month descent and ranged from locking himself away to being actively suicidal.
Now, he puts emphasis on self-awareness and understanding himself -- managing his mental health with the love and support of his family.
When you're injured, you can't play and that creates "a feeling of worthlessness," says Carlisle.
Other triggers for players can include transferring to another club or having to retire.
"You go from being fundamentally needed to obsolete, which in football usually happens at the age of 33 or 35," added Carlisle.
"There are many, many things that can contribute to a player's downward spiral in football and we need to be able to mitigate the impact."
FIFPro's 2015 research also showed that 38% of players and 35% of former players reported from suffering from symptoms of depression and/or anxiety.
'Spirals out of control'
Carlisle thinks we aren't doing enough in terms of support mechanisms and base level understanding on mental health, but does think huge steps have been made in 2018.
It's a feeling shared by another former Premier League footballer, Chris Kirkland -- a goalkeeper, who also played for Preston but is better known for keeping the ball out of the net at Wigan Athletic and before that at Liverpool.
Kirkland told CNN Sport about the troubles he faced with his mental health after leaving Wigan in 2012, which he saw as the most successful period in his career. A period he didn't want to leave behind.
"It was a big, big blow for me, I was devastated. Everybody suffers from mental health. Once you start going down that road, it's very difficult to get out of it -- it sort of spirals out of control before you know it."
Kirkland thinks real progress has only been a recent development.
"It's only really been over the last two or three years things have been moving forward but before that there was nothing there. Especially when I was growing up and during a lot of my career."
Is 2018 a year of progress?
According to the Professional Footballers' Association (PFA), the body which represents all footballers in England and Wales, by the end of August 2018, 312 football players had reached out for mental health support. That compares with only 160 players in 2016 and 403 in 2017.
Michael Bennett, the head of player welfare at the PFA, turned to a career in counseling after struggling with depression during long spells of injury as a professional footballer.
"The seed was sown then, in terms of the work I do now. Although, I don't see it as work, I see it as a calling. I played football for 20 years, it's an emotional roller coaster but what I do now far outweighs any buzz I got as being a professional footballer."
The PFA runs a 24-hour helpline for current and former players, offers a network of counselors operating to offer with emotional and mental support and is now rolling out mental health workshops to all 92 league clubs.
Kirkland praised the work of the PFA and is, himself, currently involved in the creation of a mental health app, designed to offer emotional support to people across society.
The work of the PFA, is being complimented by a partnership between the English Football League (EFL), which runs the three divisions outside the Premier League, and the mental health charity, Mind.
During the 2018/19 season Mind's logo appears on the back of the shirts of all the 72 clubs that make up the EFL.
"We're only a few weeks in but already the response has been phenomenal," said Hayley Jarvis, head of physical activity at Mind, who is also taking a lead in the partnership.
"We want this to have a lasting impact, and have a positive conversation about mental health, particularly with men. Six thousand suicides a year and 75% of them are men."
She says the charity has plans to work with every EFL club -- both on a local and national level -- all with the aim of promoting awareness and breaking down the stigma surrounding mental health.
"One in four of us have a mental health problem every year -- so for us, we are getting that message out there and trying to tackle taboos. It is OK to be not OK," she said.
"I think the fact we have the Mind logo as such a prominent feature on the back of the clubs shirts, that's really good to get that conversation started about mental health."
How powerful could that be?
For Carlisle, all these steps are positive, but he thinks football as a whole has huge potential to go even further.
"Football is our national sport, it's ubiquitous," Carlisle said. "The record number of people who watch the game and the power of the medium is incredible.
"Football has the finances and the powers of leadership to be able to create a template of support that can be then translated into any other industry in the world.
"Not only can they be flag-bearers and leaders but [football] can underpin a mental health revolution by creating the template that other industries use. How powerful could that be?"
If you're experiencing symptoms of depression the Anxiety and Depression Association of America is an international nonprofit organization providing current treatment, support and resource information. The UK charity Mind also provide advice and support to empower anyone experiencing a mental health problem.