The REAL Reasons Hollywood's Alcoholics Kicked Booze: Death Fears, Depression, Hospitalization... and Five-Day Hangovers!

The 49-year-old Hangover actor Bradley Cooper said his reasons for going sober were about wanting to achieve as much as he could in life.

He said: "I don't drink or do drugs anymore. I realized I wasn't going to live up to my potential and that scared the h--- out of me. I thought, 'Wow, I'm actually gonna ruin my life. I'm really gonna ruin it.'"

Once, he was drunk at a party and deliberately banged his head against a cement floor to show everyone how tough he was. He spent the next day at the hospital.

The turning point came when he was 29. He went to AA and "never had another drink".

The 37-year-old Game of Thrones star candidly discussed his issues with alcohol and addiction while filming the TV series and after it wrapped.

Harington said: "I went through some pretty horrible stuff.

"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."

However, he added that alongside going to rehab, he changed his thoughts.

He continued: "One of my favorite things I learned recently is that the expression 'a leopard doesn't change its spots' is completely false: a leopard actually does change its spots. 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.

"I'm a very, very happy, content, sober man."

Anne Hathaway revealed why she made the personal decision to give up alcohol.

She said: "I knew deep down it wasn't for me. And it just felt so extreme to have to say, 'But none?' But none. If you're allergic to something or have an anaphylactic reaction to something, you don't argue with it. So I stopped arguing with it."

The Devil Wears Prada star, 41, added: "As you get older, the hangovers get really bad. I put it down because the way I drink leads me to have hangovers and those were the problem. My last hangover lasted for five days."

The Oscar winner, 60, spent a year and a half getting sober after Angelina Jolie filed for divorce.

He said: "I had a really cool men's group here that was really private and selective, so it was safe. Because I'd seen things of other people who had been recorded while they were spilling their guts, and that's just atrocious to me."

Brad Pitt credits Cooper for helping him find Alcoholics Anonymous.

He added: "I always felt very alone in my life...alone growing up as a kid...it's really not till recently that I have had a greater embrace of my friends and family."

Actress and talk show host Drew Barrymore, 49, initially kept her choice to abstain from alcohol a secret, only choosing to share it with the world recently after being sober for two years – despite being open about the substance abuse issues she faced as a teenager and her stints in rehab and a psychiatric hospital.

She said: "I just want to figure this out and go about this with no profession, no public anything, and now it's been long enough where I'm in a lifestyle that I know is really working on a high road for my little journey, and there's so much peace finally being had where there were demons."

Before he became an actor, Gerard Butler, 54, was close to becoming a lawyer after going to the University of Glasgow School of Law in Scotland.

But his drinking finally caught up to him and he was fired from his job before he became a full-fledged attorney.

He said: "I used to drink until I couldn't remember anything. I was just mad for it and on a death wish. It was madness. One or two drinks was never enough for me. I was a foot-on-the-floor-all-the-way drinker."

At 25, he was unemployed and broke. He got his first role in the theater in a play at 27. He stopped drinking completely and his career took off.

He added: "It had to go. I don't miss it. Now it's as if I never had a drink in my life."

In 2012, the Olympus Has Fallen star had a stint in rehab for an issue with prescription pain pills he started taking after injuries on films. He spent three weeks at the Betty Ford Center.

Since then, he's been clean and sober.

The 35-year-old Nashville star Hayden Panettiere said: "I had to go to a liver specialist. I was holding on to weight that wasn't normally there. My hair was thin and coming out in clumps."

She went into treatment, giving herself a "blank canvas to work with" after "eight months of intensive therapy".

The actress got sober during her pregnancy with daughter Kaya but fell off the wagon after giving birth to her and Wladimir Klitschko’s baby in 2014.

She relinquished custody of Kaya amid her addiction, and is now "grateful to be part of this world again and … will never take it for granted".

The 36-year-old actor’s abs are the only six-pack this former Baywatch star Zac Efron has been working on for the past few years. He gave up drinking in 2013, and he's never looked back. He said he found freedom in sobriety.

Efron said: "I wasn't really being myself.

"A lot of my hobbies had gone out the window. Crossing the line of fear is what leads to greatness."

Harry Potter star Daniel Radcliffe explained his drinking problem stemmed from feeling lost in life.

He said: "I definitely think a lot of the drinking that happened towards the end of Potter, and for a little bit after it finished, it was panic and not knowing what to do next, and not being comfortable enough in who I was to remain sober."

Plus, he said, he simply grew tired of the blackouts.

Radcliffe, 35, continued: "I can't tell you what kind of drunk I am because I don't remember what kind of drunk I am. It's lovely. I barely think about it."

Model, Naomi Campbell, 54, opened up about her drinking problem in a segment of a documentary discussing the grief she experienced from not knowing her father and dealing with the 1997 murder of designer Gianni Versace.

She said: "You spoke about abandonment. I tried to cover that with something. You can't cover it. I was killing myself. It was very hurtful. For my mistakes, I've always owned up to them. I chose to go to rehab. It was one of the best and only things I could have done for myself at that time."

The 60-year-old star said his hard-partying with drugs and alcohol ended on May 10, 1990, after he let his family down.

Lowe said: "Back in the days of answering machines my mother called me and I could hear her voice on the answering machine.

"I didn’t want to pick up because I was really, really hungover and I didn't want her to know. She was telling me that my grandfather, who I loved, was in critical condition in the hospital and she needed my help. And I didn’t pick up.

"My thought process in that moment was: 'I need to drink half a bottle of tequila right now so I can go to sleep so I can wake up so I can pick up this phone.'"

Lowe said he knew this thinking was crazy and checked himself into a treatment center in Tucson, Ariz. He ended up loving rehab and the 12-step program that saved his life.

He said: "My life is full of love, family, God, opportunity, friends, work, dogs and fun."

The 50-year-old star Eva Mendes has always been open about her stay in rehab, saying choosing to go teetotal is a decision that should garner more support in Hollywood.

Mendes said: "The other day I was reading an article. I don't even remember who the actress was, but she's been around for a long time.

"She said something like: 'I'm proud that I've had a whole career without making it to rehab.' That’s such a negative twist on it. I'm proud of people who have the determination and the fearlessness to actually go and face their demons and get better. This is a life-or-death situation. I'm not a spokesperson, but I want to support people for their decisions when they do go in and get help."

Spider-Man star Tom Holland, 28, opened up about living a sober lifestyle – and how his well-being has improved since he ditched the booze because he was "definitely addicted".

He said he's been sober for about two years.

Tolland said: "I didn't one day wake up and say, 'I'm giving up drinking.' I just – like many Brits – had had a very, very boozy December.

"Christmastime, I was on vacation, I was drinking a lot. I decided to just give up for January... and all I could think about was having a drink. It was all I could think about. I was waking up thinking about it, I was checking the clock ... and it just really scared me."

That's when he decided he'd better give it up for good.

The 30-year-old pop superstar said at one point in his life he began depending on marijuana heavily and later got involved with alcohol, taking pills, MDMA, psychedelic mushrooms and "everything".

Justin Bieber eventually decided he wanted to get sober when he "felt like I was dying".

He said: "My security and staff would come into my room at night to check my pulse."

Things were looking bad, but then the Never Say Never singer was arrested in Miami Beach in 2014 and charged with DUI, resisting arrest without violence and an expired driver's license.

He was able to avoid jail time by pleading guilty to a lesser charge of reckless driving.

Bieber added: "It was not my finest hour. God has brought me a long way. My encouragement to you is to let your past be a reminder of how far God has brought you. Don't allow shame to ruin your today. Let your life blossom into all it should be."

The 46-year-old Mad Max: Fury Road star Tom Hardy said he started drinking and sniffing glue at age 11.

He was in constant trouble in his teenage years, experiencing many run-ins with the police. Some of these resulted in juvenile jail.

At 16, he was abusing drugs and alcohol. He was arrested for car theft and possession of a gun, but the British court ended up dismissing the case. After a wild night out partying, he woke up in a London street lying in a puddle of his own blood and vomit. That morning, the doctor who treated him laid it out in black and white.

Hardy said: "I was told very clearly, 'You go down that road, Tom, you won't come back. That's it. All you need to know.' And that message stayed with me clearly for the rest of my days."

He went to rehab that same year, and successfully completed the 28-day program.

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