Within a decade David Vaughan went from serving his Queen and country to serving a four-year prison sentence at HMP Norwich.
The 36-year-old developed severe Post Traumatic Stress Disorder (PTSD) after leaving the armed forces in 2005, and struggled to adjust to civilian life.
After multiple suicide attempts, a crippling drug addiction and spiralling debt, he was jailed in 2014 for fraud.
But it was during his time behind bars that Mr Vaughan, who previously lived in Lowestoft, realised things needed to change.
And after seeking help from the Norwich-based veterans charity The Walnut Tree Project, the father-of-two managed to turn his life around.
Today, he is not only clean from drugs, but he is back in full-time employment in London.
And now, he is planning to undertake a charity sky dive to support the organisation which he believes saved his life.
He said: 'Certain things in life can make or break you, and by going to prison I hit rock bottom.
'But it became the solid foundation in which I rebuilt my life and made me into the person I am today.
'I was determined to change and nobody is going to stand in my way to achieve my goals.
Mr Vaughan joined the armed forces, aged 17, in 1998 to escape a troubled upbringing.
He initially joined the Royal Navy, but later re-trained and was involved in operational theatres including Sierra Leone in 2001.
Although his training made him physically and mentally strong, his time in military began to have an impact.
'I started to have really bad flash backs and night terrors,' he said. 'I was suffering from black-outs and began drinking quite heavily.
'The way the military worked back then was, rather than paying for the resources to help you, it's was easier just to kick you out.'
Mr Vaughan was medically discharged in 2005 and given a military pension of just £26 per week.
He said without any aftercare from the Ministry of Defence, he struggled to cope in the civilian world.
'I reached out to my local GP and was misdiagnosed on numerous occasions with anxiety and depression,
Then in 2013, Mr Vaughan suffered a mental breakdown and attempted to take his own life.
'I had an amazing daughter and a loving wife, but that wasn't enough as I felt I couldn't cope anymore,' he said.
'I tried everything to get support for my family by way of benefits, but I was always turned away because of a military pension I received.'
Mr Vaughan said he had become 'hideously' addicted to cocaine, which put a strain on his marriage.
As he spiralled into debt, he committed fraud, and was jailed for a combined sentence of four years.
He said: 'The morning I woke up in prison I looked at myself in the mirror and said 'it doesn't get any worse than this'.
'I immediately self-referred for mental health and NHS wellbeing for extra help.'
During his time inside, he gained 15 different qualifications in construction and underwent psychotherapy for his PTSD.
In 2016 he was also refurbished the Britannia Veterans' Centre, next to Norwich Prison, in just 28 days.
On his release, Mr Vaughan sought help from the Walnut Tree Project and its founder Luke Woodley, and enrolled on a 16 week veteran's stabilisation programme.
'I was still a broken man when I came out of prison last year, and it was down to Luke and his own expertise that got me through it.
'If it was not for him and his charity, I would either be back in prison, or dead.
'I took what I needed from the course and it kind of gave me a new lease of life.'
Today, Mr Vaughan now works in London as a Programme Manager for a global construction firm.
'There is no easy way to do a prison sentence, he said. 'I did it through true grit and the determination to be a better and happier person.
Try a little hope and self-belief and you will be amazed in what you can achieve.'
Later this year Mr Vaughan will be undertaking a free fall charity parachute jump at Ellough Air Field in Beccles to raise money for the Walnut Tree Project.
It comes as the charity last month revealed it could have to cut back one of its services due to a lack of funding.
To donate to the parachute jump, visit: www.justgiving.com/crowdfunding/david-vaughan-10000ft
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