'Game of Thrones' star Kit Harington 'lost his way' before rehab

Claims have emerged that Kit Harington had "lost his way" before checking into a treatment facility.

The 32-year-old Game of Thrones star checked into a treatment facility last month after the ending of the hit HBO show - on which he starred as Jon Snow - "really hit him hard", and now a costume designer for the program has said it was clear leaving the show behind affected him, because he was always a "sensitive soul".

Costume designer Michele Clapton told Us Weekly magazine: "They were children when they started. And it became such an enormous thing, and I think when you stop, it's sort of a huge security blanket is taken away.

“I mean, they all became friends with each other, and then suddenly, there's nothing to go back to. So I would imagine that had something to do with it. He lost his way a bit.”

Michele said that Kit was a “sensitive soul” who visibly upset in the final real through, but she’s “sure he’ll be ok”.

Kit checked into Connecticut's Privé-Swiss wellness facility after self-referring himself to the centre last month to work on some "personal issues".

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"Kit has decided to utilise this break in his schedule as an opportunity to spend some time at a wellness retreat to work on some personal issues,” his representative said at the time.

A source told the New York Post newspaper's Page Six column: "The end of 'GoT' really hit Kit hard.

"He realised, 'This is it -- this is the end', it was something they had all worked so hard on for so many years. He had a moment of: 'What next?'

"He's in the clinic predominantly for stress and exhaustion and also alcohol."

The insider said the British actor has the full support of his wife, former co-star Rose Leslie.

The star recently admitted he had a "full-on breakdown" after filming his final scenes for the show.

"My final day of shooting, I felt fine ... I felt fine ... I felt fine ... then I went to do my last shots and started hyperventilating a bit ...Then they called 'wrap' and I just f***ing broke down,” he told Esquire.

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“It was this onslaught of relief and grief about not being able to do this again."

From Yahoo Lifestyle AU, with additional reporting by Bang Showbiz.