“But I made them into a dream, a vision, and added one false bit where he got hit by a vehicle. I believed it 100%.”

The vision released him, to an extent, from the torture that pulled him in opposing directions, and demanded answers, all of which were met with electric shocks. Envisioning and believing Stephen was dead was the only way Gavins could psychologically escape.

But he had to prove it. He went online and scoured the death records for 1972. There were none for a Stephen Carmel Routledge.

Stephen did not die.

“I thought, ‘Waaaaaaaayyyyyyyyyy!!” he says, whooping with delight at the discovery. He rang his friend Malcolm. “I said, ‘I’m going to find him. I don’t care where he is, I’m going to find him.’”

He went online again, using 192.com to try to find Stephen’s address but the unusual name did not materialise in any searches. For three days he looked and found no mention of him. He wondered if he had gone abroad. But before widening his search he looked at death records for other years, just to make sure.

There were two results under Stephen Routledge. The second one was his Stephen.

“He died on 20 October 1983,” says Gavins – 11 years later than he had previously thought. “I went from high to low in three days. One minute he was alive, and then dead again.”

Gavins picks up a diary from 2011 and reads the entry he wrote that day: “My Stephen is dead. I love him and I’ll love him forever… I need to find out how he died… I need a reason not to kill myself. I’ll just have to keep thinking of Stephen. That will keep me alive.”

Determined to uncover the circumstances of his death, Gavins rang a local priest back in Keighley who would have known the Routledge family. “The priest said, ‘The only thing I know is Stephen died in a car crash, on the M6.’”

Gavins began pouring through local newspapers in case the death had been reported. He found an article.

“He was driving back from Bolton to Blackburn,” he says. “A police car started following him and flashed him to stop. Stephen thought he was over the limit, so instead of stopping he drove away. They police chased him, and coming into Blackburn there’s a curve. He lost it. The car rolled. There was another car coming the other way. He died in hospital.”

The similarity of the circumstances of Stephen’s actual death to how Gavins had envisioned it during dissociation is, he says, a horrible irony. He stops again and looks out the window at the drizzle now falling over the Cumbrian hills. After the news of Stephen’s death, so soon after thinking he was alive, Gavins fell into another depression.

He never found anyone else to love.

“If anyone comes near me I back off completely,” he says. “I just don’t want closeness at all.” Sometimes he goes to gay clubs, but he can’t cope with much more – the aversion therapy made him anxious all the time, he says. He hasn’t had sex in 15 years.

In 2015 his mental health began to improve thanks to a new treatment for post-traumatic stress disorder he received on the NHS called eye movement desensitisation and reprogramming (EMDR). The technique, now widely recognised, uses back-and-forth eye movements during sessions to sever traumatic memories from intense feelings.

He has also learned about the theory of body memories, whereby experiences are believed by some to be stored physically rather than mentally. Understanding this concept helped alleviate the shooting pains in his arm and shoulder, and the shocks he would feel when lying down. He also came to realise how widely the trauma had spread across his life.

“I never knew why I don’t use slippers, I don’t own a dressing gown, I don’t wear a watch, and every single shirt I have is either a T-shirt or very loose cuffs,” he says. He could not bear anything around his wrists because it invoked the feeling of being strapped down. Slippers and dressing gowns take him back to that room, too.

But now, he says, “I’m in a different world.” He walks a lot, and goes climbing across the Lake District. The instinct to end his life has gone, in part from a recent ice-climbing accident where he was faced with a choice: to let go and die or to cling on and fight. He chose the latter, and continues to do so. There is a phrase he repeats to himself that helps to keep him going if he becomes overwhelmed: “I want to see what happens next.”