'It was toxic': Liam Payne says he was addicted to 'pills and booze' during 'One Direction' fame

Liam Payne is opening up with his struggle with addiction and mental health.

The "One Direction” alum revealed that he "didn't like myself very much" during his early boy band days, which he said were filled with "pills and booze" and "moments of suicidal ideation."

"There is some stuff that I’ve definitely never spoken about," the 27-year-old told "The Diary of a CEO" podcast host Steven Bartlett Sunday. "It was really, really, really severe. It was a problem."

Payne catapulted to fame at age 16 in "One Direction" alongside Harry Styles, Niall Horan, Louis Tomlinson, and Zayn Malik in 2010 when the group competed on "The X Factor," after unsuccessfully competing as solo artists. The group, one of the best-selling boy bands of all time, went on hiatus in 2015.

"The day the band ended, I was like, 'Thank the Lord,'" Payne said. "I know a lot of people are going to be mad at me for saying that, but I needed to stop or it would kill me."

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Payne said he struggled with alcoholism at the peak of the band's success, when he spent a lot of time traveling during four world tours.

"In the band... the best way to secure us, because of how big we’d got, was just to lock us in our rooms. What’s in the room? A mini-bar," he said. "So at a certain point I thought, I’m just going to have a party-for-one and that seemed to carry on for many years of my life. Then you look back at how long you’ve been drinking and you’re like, 'Jesus Christ, that's a long time.'"

The "Strip That Down" singer continued: "It was wild but it was the only way you could get the frustration out."

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Payne said that although it seemed "One Direction" could do anything they wanted from an outsider's perspective, he often felt "trapped" in "lonely hotel rooms," which he said "really (expletive) me up."

"We were always locked in a hotel room at night," he recalled. "Then it would be car, hotel room, stage, sing, locked. So it looked like they pulled the dust cloth off and let us out for a minute and then back underneath it."

He continued: "There were points where it was toxic and difficult. Don't get me wrong, we had the best time ever, but… you don't realize you have a choice at that point."

Payne, who's been "sober for just over a month," said the group's tremendous success came with "sacrifice." He said his young stardom "deluded" his growth: "You leave fame the age you entered it."

"I was a director of a half-a-billion pound industry at 22… But if I am trying to pay car insurance, I am useless. You don't grow in other aspects of your life because you have people do crap for you," he explained. "Picking up my post? I am the worst person in the world."

He added, "I still feel like a child in so many ways. There is no link between money and happiness. It is a myth. Money is the ability to relax on certain things."

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When describing his relationship with his former bandmates, Payne says it's "great with most of them," particularly Styles.

"I had a lovely phone call from Harry the other day," Payne said. "He was checking in on me. It's almost as if some people have got a sixth sense about when you're going through something and want to check in."

Payne called Styles a "lovely, lovely boy," adding, "I love him to pieces."

He shares son Bear, 4, with British pop star Cheryl Cole. During the Sunday podcast episode, the singer confirmed that he ended his engagement to model Maya Henry after 10-months.

"I am indeed (single)," the star said. "I feel like more than anything at this point, I’m more disappointed in myself that I keep on hurting people. That annoys me. I’ve just not been very good at relationships."

He added, "I'm just not very good at them so I just need to work on myself before I put myself on to somebody else."

If you or someone you know may be struggling with suicidal thoughts, you can call the U.S. National Suicide Prevention Lifeline at 800-273-TALK (8255) any time day or night, or chat online.

Crisis Text Line also provides free, 24/7, confidential support via text message to people in crisis when they dial 741741.

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This article originally appeared on USA TODAY: Liam Payne struggled with addiction during 'One Direction' fame