When Michael Langton's property business failed, he descended into depression.
Like many others his age he couldn't get back into employment and so began suffering from anxiety and low self-esteem.
The 26-year-old is now back working after a year unemployed - but a study has revealed there are many others going through similar problems.
The Prince's Trust says increased numbers of young people in the south- east are suffering from mental health problems which have been brought on by unemployment.
One in four 16 to 25-year-olds suffers from insomnia, more than a fifth have self harmed and one in five feels depressed 'all' or 'most' of the time, according to the findings.
The study, based on interviews with 2,170 young adults, shows those who are not in employment, education or training are more likely to encounter these symptoms.
Michael Langton, a qualified engineer, of Twyford Avenue, Stamshaw, said: 'At the time there was very little demand for engineers and I struggled to find any job at all.
'Being out of work really got me down. I felt like I had no goal in life.
'Christmas and birthdays were the worst. It was awful not being able to buy a present for your girlfriend or family.'
Michael eventually enrolled in the Prince's Trust Get Into Maritime scheme - a project helping young people find work in the maritime industry. He now works for Gosport-based Clipper Ventures, recommissioning race yachts.
'The course was a real lifeline for me,' added Michael. 'I got to meet new people, learn new skills and the Prince's Trust funded my yacht crew training. I really enjoy my job.'
The charity also revealed the long-term unemployed are 'significantly' less happy across all areas of their lives. It comes as a report by the Trades Union Congress in June last year revealed 240 young people in Portsmouth had been claiming Jobseekers Allowance for more than six months.