Media playback is unsupported on your device Media caption James says playing football helped him face "his demons" after his dad committed suicide.

It was the day of James Casling's fifteenth birthday when his father killed himself. It left the teenager in a dark place - he was sectioned three years later after trying to take his own life countless times. But a simple offer to play football changed everything.

Shaking as he speaks, and trying to collect himself amid the tears, James relives the last few years of his father's life.

His story is understandably still very raw.

On 20 May 2010, James should have been celebrating turning 15, but instead, he learned that his father had taken his own life.

It is an event he is still grappling to come to terms with.

"I always wondered why he would do it, why my love for him wasn't enough," he tells the BBC's Victoria Derbyshire programme, not afraid to open up about the most troubling of thoughts.

"But then I realised, if someone's like that [suicidal], I couldn't have saved him.

"I think that hurts a lot more, to know there was nothing I could have done to stop it."

Image copyright James Casling Image caption James with his father

His father's suicide left him in a "dark place"- his whole world turned upside down, as he describes it.

"I was in so much pain, that to carry on [living] seemed like it was going to hurt more than to end my life."

Over the next three years, James tried to kill himself on multiple occasions.

"It's a scary place. People say 'are you afraid of dying?' But if you can take steps to end your life, there is not much that is scary to you."

Speaking from his own experience, he says it is often not sadness that leaves people wanting to kill themselves, but the way they wrongly view their life as worthless.

"To sit in a room and be left alone with my thoughts, I think that's what kill people.

"It's their own head, telling them their life isn't worth it, when in fact it is."

Top goalscorer

Aged 18, James was sectioned and admitted to the Park Royal Mental Health Centre in north-west London.

It was there, with the help of the QPR Community Trust, that his life changed.

James recalls being asked one morning if he wanted to play football.

He immediately said yes, leading his mother to take the simple step of buying him a pair of football boots.

"At the time I didn't realise, but if my mum didn't buy me those boots, things might not have changed, and I might have lost my life to mental illness."

Image copyright James Casling

Playing for the QPR Community Trust's mental health team, James became the club's top goalscorer in the first three seasons - an achievement about which he is rightly very proud.

But he also gained something more - a belief in himself.

"When I lost my dad, I lost all sense of belonging. It threw me out of control. I didn't have anything I felt I belonged to.

"When I put on my kit and play with my friends, it feels like we're not just friends, we're family.

"Every week I attended training and it gave me hope I could be someone my family and friends could be proud of.

"Every week I would put so much effort in I couldn't walk afterwards."

In his strikingly frank and endearing manner, he adds: "It made me want to stay alive, so my mum and brothers wouldn't have to bury me."

Image copyright James Casling Image caption James says his father's suicide left him in a "dark place"

James - supported by his mother and the Mental Health Football Association - hopes others can feel the same benefits in future.

"We can never stop people getting mentally unwell, but we can help them get better [through] football.

"If I had carried on that path [from before football] I wouldn't be here today. I had to stop destroying myself."

Although he is now older, he is unsure what the future holds for him - but remains positive.

"The future's looking a lot brighter than it was a couple of years ago.

"I'm 21 now, I've got a good 60 years ahead of me."

His hope is that by speaking out, others will be inspired by his story too - and may seek help.

"I've just got to be strong and help people come out of their darkness."

Watch the Victoria Derbyshire programme on weekdays between 09:00 and 11:00 on BBC Two and the BBC News Channel.