Martin Pratt, who served during the 1970s and 1980s, developed severe nightmares and flashbacks following the death of his mother – 30 years after he saw service in Northern Ireland.
The grandfather’s life spiralled into depression and alcoholism as he battled against the illness, before he died in August at the age of 59.
However, his widow, Suzan, believes his training with the SAS meant it was impossible for psychotherapists to help him.
She said the “tough” culture and image of soldiers serving with the SAS meant that mental health problems were a taboo, but given they were often placed in violent and traumatic situations, the need for help was probably greater than anywhere else in the armed forces.
To dispel any myths that seeking counselling is a weakness, soldiers within the SAS should be obliged to take up psychological help, the retired headteacher said.
She also believes civilian doctors do not understand enough about PTSD and the current system, which meant that Mr Pratt could not receive mental health treatment while he was drinking, had failed her husband.
Mrs Pratt, 55, from Lincolnshire, said: “I met a doctor who had served in the SAS and he said to me that it takes a special kind of person to even want to apply to get in.
“Only a small percentage are successful and then they receive training. By that point it’s very difficult to get through to them. Counselling is not the thing for them to do as it’s not part of their image.
“Their culture is not to be seen to be weak, and that’s why counselling should be compulsory.”