The 24-year-old X Factor finalist said that after a traumatic childhood spent in and out of foster care, he became withdrawn and started to feel dependent on drink.
"This time last year was the darkest point in my life," he told Look. "I wanted to be making music and I wasn't, so I cut myself off from everyone and I was in a bad place."
The singer was diagnosed with anxiety and depression, but decided he didn't want to take medication.
"I'd stay in my bedsit on my own or get obliterated [on drink] to try to forget about it," he explained. "I felt ready to give up on life. I didn't want to jump off a building, but who knows how bad it could have got?"
Arthur's father left when he was just 2 years old, and at the age of 15 the singer himself left home, meaning that he had little contact with his parents while growing up.
"I lacked a male role model, and I didn't want to listen to what he had to say because I felt he wasn't there for me," Arthur continued. "But now I understand more about it, and get on really well with both my parents."
Arthur added that when he finally decided to audition for The X Factor after years spent gathering his courage, his father was there to support him.
"I asked mum and dad to come to my X Factor audition, and it was the first time that they'd been in the same room in years," he said. "Since then they've got on really well - it's strengthened my relationship with them."
Adding that he is feeling more positive than ever, he said: "I've got my confidence back. My attitude's been rejuvenated.
"The X Factor saved me. It's helped me beat my demons, and I know I'll never let that happen again."
Photo gallery - 'The X Factor' semi-final results show in pictures:
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