A former Royal Marine who suffered from post-traumatic stress disorder (PTSD) shot himself while working as a security officer in Afghanistan, an inquest has heard.

Stuart McBrearty, 39, from Aldershot, Hampshire, was found dead in the shower of his accommodation at the Canadian embassy in Kabul on 17 October last year.

Hampshire coroner Jason Pegg said McBrearty had visited a psychiatrist, Dr David Oyewole, at the private Nightingale Hospital in London a month before his death and told him that, during his periods of service in Iraq and Afghanistan, he had a “number of horrific and frightening experiences”.

He said this had involved members of McBrearty’s team “being injured or killed” and Oyewole had diagnosed that McBrearty had “PTSD with possible superimposed depression”.

He said McBrearty, who also had a difficult childhood, showed signs of being “hyper-vigilant, extremely anxious” and suffered “intense thoughts and dreams about combat”.

The coroner said McBrearty had served with the Royal Marines before leaving in 2013 to become a close protection officer and at the time of his death was working at the Canadian embassy in Kabul for the Olive Group, part of the security firm Constellis.

Pegg said a postmortem examination showed that McBrearty, who carried a pistol at all times, had suffered a gunshot wound.

A toxicology report had showed McBrearty had been more than three times the drink-drive limit and also had therapeutic levels of diazepam, a drug used for depression and anxiety, in his system.

The inquest was told the company had a zero-tolerance policy to alcohol but drink could be obtained in Kabul.

Pegg added that McBrearty’s GP said he had been diagnosed with depression in 2000 and had taken a medication overdose in 2003 and suffered a shrapnel wound to his buttocks in 2008.

McBrearty’s widow, Sophie Hughes, said: “He was always professional, funny, but troubled.”

She said he had called her 48 hours before his death, saying he wanted to end their marriage, and described him as “mentally broken and unstable” despite a recent promotion.

Stephen Ronald, a former colleague who contributed to the inquest from Afghanistan, told the hearing McBrearty had appeared “stressed” and had been experiencing “financial, work and home pressures” as well as having feelings of guilt over the death of a colleague.

Recording a verdict of suicide, Pegg said McBrearty was described as “one of the best” and added: “Clearly very much a great man who had his demons.”

The inquest was held via video-link because of the Covid-19 lockdown.