One of the first police officers on the scene of the London Bridge terror attack has said he was left with post-traumatic stress disorder.
PC Leon McLeod ran towards the scene as three men carried out a van and knife attack in June 2017, killing eight people.
He said that his life "unravelled" in the following year.
"I was a dad, I was married, a homeowner. Essentially, I threw all those things away."
He added: "I just wasn't alright. Something in the back of my head was justifying these things and I was just reckless."
PC McLeod, who was awarded the Queen's Gallantry Medal, chased the attackers from the scene before treating the wounded.
He said he could not discuss the details of his actions that night, which ended when police shot dead the three attackers, ahead of a coroner's inquest.
PC McLeod, who was born in Ashford, said it was only when he began therapy a year later that he began to face up to the psychological toll.
"Within a month I was suffering from anxiety," he said. "I was really difficult on my partner at the time, I was drinking more, but I just didn't really acknowledge that something was wrong."
PC McLeod, who is running the London Marathon this weekend in aid of emergency services support group PTSD999, said that life was "a lot better" after months of therapy provided him with "the tools to try and look after myself".
The British Transport Police officer said he had received "a lot of support" and advised others who had encountered trauma not to ignore the "tell tale signs".
"It's about addressing it," he said. "If I had done that I would probably still be with my wife [and] would still have my little boy around as well."