'Go hard or go home,' that was the motto my friend lived by. James Mabbett. Mabs to his mates.

Aka an infectious lust for life, bloke you wanted to be around, life and soul of every party. TOTAL. LEGEND.

Painting this picture isn't to sensationalise his character in death by making him more grandiose than he was, nor is it to fall into the predisposition of glossing over his bad habits as we do when honouring the dead.

It's simply to emphasise that mental illness lurks in the unlikeliest of places. That the 'happiest' in the room could be the saddest. And that a smile can mask a lot.

We are not visionary doctors, we cannot see who is sick. It is not the Jack Nicholson lookalike circa One Flew Over The Cuckoo's Nest frothing at the mouth in a straitjacket we need to be watching out for, but those closest to us.

I was at work the Monday after Valentine's Day when I got 'the call'. It took another week to find out exactly what had happened.

Crippled by shock, I found 'comfort' by convincing myself Mabs had partied too hard during his work weekend away, taken alcohol to the extreme, and in a macabre way at least he passed away while celebrating like the night owl he was.

He categorically 'is the last person on earth who would take his own life' I fiercely told people.

Six days later while working in America and getting ready for the Academy Awards, I learned over WhatsApp that dearest Mabs – a 24-year-old uni graduate who oozed charisma out of every pore and had you in stitches with his random acts of hilarity – after a relatively calm night with colleagues, his alcohol limit was found to be well below the national driving acceptance level with no drugs in his system, had quietly hanged himself in a hotel room.

I don't remember much about the day, other than sobbing in my boyfriend’s arms, graffiting Mabs’ name all over my Oscars memorabilia, and that it was pelting down with rain. Rare for LA.

As it began to sink in, what followed was indescribable grief: see-sawing between a blank out-of-body experience and the brutality of an axe to the heart. Then flooded in the endless cyclone of questions: what was going through his head during those final moments alone; if only he had just reached out; how did I not spot the signs? HOW?! I work in mental health, FFS.

I suddenly became aware that the nights we had spent together, my heavier, more intimate conversations had always been with friends that I knew were suffering as they had confided in me. I spent time talking to them about their troubles or issues at home, Facebooking the next day to check they were okay.

I realised I hadn't been paying attention to Mabs in that way as I was under the impression he was fine as he never said anything to the contrary.

While he had a sensitive side to his character, and the ability to sense when others around him were low and react in an empathetic and supportive way, we shared the same party animal gene and I saw him as my No1 tequila buddy.

Maybe that was the problem (and the clue, moving forward) that having one emotion – even if it's happiness – is unheard of and should flair up warning flags.

When I flew back to the UK, consumed by sorrow and trapped in the surrealism of it all, I also felt a fire in my belly to actively do something. A spark had ignited to not let his death be for nothing. That in spite of the tragedy, a powerful legacy for Mabs could be to help others.

I began devouring information, reading about suicide, dropping his name into any and every conversation, tweeting him when down the pub, even though he wouldn't see the tweets, I was determined to not forget and even more determined not to shy away from the truth.

On a night out with The Self-Esteem Team, the group I work with who go into schools teaching students on mental health, body image and self-esteem, we started throwing ideas around about what we could do to get the message out there that suicide is now the biggest killer in men under 50.

Mental Health Awareness: Facts and figures Show all 10 1 /10 Mental Health Awareness: Facts and figures Mental Health Awareness: Facts and figures Mental Health Foundation: Living With Anxiety report 30 per cent of people deal with anxiety by talking to a friend or relative, or by going for a walk. Getty Mental Health Awareness: Facts and figures Mental Health Foundation: Living With Anxiety report Almost one in five people feel anxious all or a lot of the time. PA Mental Health Awareness: Facts and figures Mental Health Foundation: Living With Anxiety report 22 per cent of women feel anxious a lot or all of the time, compared to 15 per cent of men. Roman Levin/Flickr Creative Commons Mental Health Awareness: Facts and figures Mental Health Foundation: Living With Anxiety report 45 per cent of people who feel anxious in everyday life cite financial issues as their biggest cause of worry. Getty Mental Health Awareness: Facts and figures Mental Health Foundation: Living With Anxiety report And 26 per cent of people who feel anxious say fearing for the welfare of their children and loved ones leaves them burdened with worry. And 26 per cent of people say fearing for the welfare of their children and loved ones leaves them burdened with anxiety. Mental Health Awareness: Facts and figures Mental Health Foundation: Living With Anxiety report 27 per cent of people who suffer from anxiety say work issues, such as long hours, are the source of the problem. Getty Mental Health Awareness: Facts and figures Mental Health Foundation: Living With Anxiety report But 16 per cent use alcohol to cope, while 10 per cent turn to cigarettes in the face of anxiety. Unemployed people are more likely to resort to these harmful strategies: 27 per cent use alcohol and 23 per cent use cigarettes. AFP/Getty Mental Health Awareness: Facts and figures Mental Health Foundation: Living With Anxiety report Only seven per cent of people who say they suffer from anxiety seek help from their GP. Getty Mental Health Awareness: Facts and figures Mental Health Foundation: Living With Anxiety report People are thought to be more anxious than they were five years ago. Alessandra/Flickr Creative Commons Mental Health Awareness: Facts and figures Mental Health Foundation: Living With Anxiety report The stresses of modern life are thought to have created "The Age of Anxiety". Getty

During Mental Health Awareness Week, we agreed that this would be the ideal platform to launch a campaign in which we’d encourage men to talk openly about their anxieties in a bid to stamp out stigma.

So with three merry brains swimming in All Bar One wine, our Switch On The Light embryo was hatched. Mabs would be chuffed. He often favourited our Twitter posts, a silent nod of approval that he liked what we stand for.

We created a wishlist and started pinging emails out to high-profile men, asking for their help in tackling the horrifying fact that one in every four male deaths in men aged 20-34 in the UK is from suicide.

With depression a subject close to his heart, and having attempted suicide himself, Stephen Fry said yes immediately. Our text message exchange was a littering of expletives in celebration as we realised this video could have the power to reach thousands of people, being a megaphone to those in need.

We then secured Clarke Carlisle, someone football enthusiasts look up to for being so vocal about his struggles despite a background where feelings are branded 'girly' or 'gay' in a culture where beer, sex and scores dominate.

Ian Royce, who warms up The X Factor and Britain's Got Talent crowds before the show, was next to jump aboard. A fitting tribute to Mabs from a fellow comedian who spends his life with a grin etched on his face disguising the fears within.

Giving a voice to music fans is chart-topper and Deaf Havana frontman James Veck-Gilodi, who shares his thoughts in a brutally honest video even though he was too embarrassed to show his own girlfriend, telling her she had to wait until the official video launch to see it.

Our baby of the bunch is YouTube sensation Charlie McDonnell, the first in the UK to reach one million subscribers, who relates to the teen generation as he addresses the pressures of social media and our innate human yearning to be liked.

Professor Green, recently announced as the patron for suicide prevention charity CALM, joined us having been affected by death seven years ago when his father took his own life. Completing the line-up is TV presenter Ortis Deley.

We learn about physical health with biology and PE, yet a person is not complete without their mental health (no one is a headless body), so we should be teaching our future generation how to nurture theirs. There is no point in just teaching facts if we don’t equip people with the skills of how to cope in life.

As someone who battled self-harm for two decades, I understand what it's like to feel as though you have no one to talk to. I know what it's like to feel overwhelmed by the concrete walls caving in, utterly hopeless as the agony festers inside because you don't have the words to article it.

That sheer desperation, of nowhere to turn, fearing that people will either dismiss you and say 'pull yourself together' or march you off to the nearest psychiatric ward. The myth still lingers that it's deeply humiliating to admit you cannot cope, it makes you look weak, casts you as a failure.

If there's one message viewers take away from our video, it's that seeking help is one of the strongest, bravest things you can possibly do. You don't have to suffer alone. And speaking out really is the first step to making things better and saving you from yourself.

While I can never know what it was like to walk in Mabs' shoes, I am beginning to realise that he didn't necessarily want to end his life, but that he just wanted to end his pain.

The silver lining, if you can call it that, is that I have found a friend in his mother and sister. And while The Self-Esteem Team may have done the coordinating, Switch On The Light is all down to Mabs. There is no doubt in my mind that his story will now go on to save a life.

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