His wife, Rose Leslie— who he met on the set of the series and played Jon Snow's Wildling companion, Ygritte— is said to have been "extremely supportive" of his decision to seek help.
“He’s in the clinic predominantly for stress and exhaustion and also alcohol," a source close to the star told the outlet. "Everyone close to him really wanted him to get some rest. Right now, he just needs peace and quiet.”
It's no secret Harington has struggled with mental health issues and has been open about his battle with depression. He recently told Variety that his path to stardom has been riddled with hiccups and his lowest point came when his character was killed and then came back to life.
“It wasn’t a very good time in my life,” he said. “I felt I had to feel that I was the most fortunate person in the world, when actually, I felt very vulnerable. I had a shaky time in my life around there — like I think a lot of people do in their 20s.”
“My darkest period was when the show seemed to become so much about Jon, when he died and came back,” he explained. “I really didn’t like the focus of the whole show coming onto Jon — even though it was invalidating my problem about being the weak link because things were about Jon."
He added: “When you become the cliffhanger of a TV show, and a TV show probably at the height of its power, the focus on you is f—ing terrifying. That was a time when I started therapy and started talking to people,” he said, “I had felt very unsafe, and I wasn’t talking to anyone.”