The 34-year-old told the outlet that some difficult things have happened to him since GOT ended in 2019, and things "that were happening during Thrones, were of a pretty traumatic nature and they did include alcohol."
"You get to a place where you feel like you are a bad person, you feel like you are a shameful person. And you feel that there's no way out, that's just who you are," Harington explained. "And getting sober is the process of going, 'No, I can change.'"
"One of my favourite things I learnt recently is that the expression 'a leopard doesn't change its spots' is completely false: that a leopard actually does change its spots. I just think that's the most beautiful thing," the actor said. "It really helped. That was something I kind of clung to; the idea that I could make this huge fundamental change in who I was and how I went about my life."
In May 2019, he checked into the Privé-Swiss retreat in Connecticut where he said he was treated for "mainly alcohol."
"I will say about my addictions that I kept them very, very quiet and I was incredibly secretive and incredibly locked up with them. So they came as quite a surprise to the people around me. Which is quite often the case, I guess," he admitted, noting his addiction was stressful for his wife and fellow GOT alum Rose Leslie.
"Like all of us, I have been an arsehole," he said of how his friends handled his addiction. "I’ve been incredibly privileged to have some real f*****g pricks as friends who told me the truth. Someone said to me once, 'When you’re sitting at a table and everyone around that table you’re paying, that’s when you know you’re in trouble.'"
The Pompeii star admitted that his only vice now is tobacco, which he is also trying to kick.
However, things had been so dark at one point where he considered taking his life. "I went through periods of real depression where I wanted to do all sorts of things," he said, adding that he hoped that sharing his story would "maybe help someone, somewhere. But I definitely don't want to be seen as a martyr or special. I've been through something, it's my stuff. If it helps someone, that's good."
Harington and Leslie tied the knot in 2018 before welcoming their son in February. The Eternals star admitted that the first three months after the couple welcomed their first child was "slightly torture" and "a kind of hell."
"There's something about having a child that is the most physically draining thing," he shared. "My hat goes off to any single parent. Any single parent, you're a f*****g genius. I don't know how you do it. Because it's more exhausting than everything I did on Thrones."
Harington has since gotten the hang of fatherhood and said that life is "wonderful" now. "I have a child and my relationship is brilliant … I'm a very, very happy, content, sober man," he gushed.