09/25/2013 01:46 EDT | Updated 09/25/2013 02:13 EDT

Backstreet Boys' Nick Carter On Being Blamed For His Sister's Death, His Own Addictions And Reality TV (EXCLUSIVE)

Nick Carter

For three hours Nick Carter lay on the bathroom floor bawling at the news of his younger sister Leslie's tragic death. The 33-year-old Backstreet Boy was in the middle of a U.S. solo tour when he received the devastating news.

"I was on my tour bus and I got a call from my dad and he said, 'There's been a death in the family,'" the singer tells HuffPost Canada Music. "I was dumbfounded. Shocked."

"At the same time I knew something like this would happen in my family one day… and I couldn't stop it to save my life. No one would listen to me, which is why I had to start leading by example and doing better myself."

While Nick had drastically turned his life around following a battle with drugs and alcohol and tried many times to help Leslie do the same, she resisted his support and he became wary of spending time around her since he was trying to stay clean himself.

He hadn't seen his 25-year-old sister -- who was reportedly suffering depression and whose parents had been trying to get diagnosed with bipolar disorder -- for nearly a year before her January 2012 death from a suspected prescription drug overdose.

At the time, tabloids blasted Nick for missing the funeral but behind the cruel headlines his grief was deepened by his patchy relationship with his family, who immediately blamed him and the fact he distanced himself from Leslie, for her death.

"I was so upset because I wanted to go to the funeral so badly. But I was ganged up on and made to feel like it was my fault. It was wrong in so many ways."

Fearful that being surrounded by blame and negativity would cause him emotional scarring at a time when he was still working to keep his life on track, Nick reluctantly decided not to attend. Instead he said goodbye to Leslie "in my own way -- talking to God and having my own moment of silence" -- and continued to tour, relying on his cathartic haven of the stage to help him mourn.

Interview continues after slideshow

Photo gallery Backstreet Boys Photos See Gallery

Nineteen months on, Nick has dedicated his new book "Facing the Music and Living to Talk About It" to Leslie. In the autobiography and self-help hybrid, he hopes his struggles with addiction, family and stardom will help others find their way through difficult periods.

In the book, he write "I began drinking heavily in my teens and then moved on to drugs at eighteen or nineteen, starting with marijuana and moving up to cocaine, Ecstasy, and prescription painkillers among other substances."

While he regrets not being able to hand the book to Leslie, he believes many of their problems stemmed from their childhood in Florida, where now-divorced parents Robert and Jane were heavy drinkers and constantly fighting.

By night, the kids fearfully listened to furniture breaking or glasses smashing and by day Nick babysat while his parents worked.

When twins Aaron and Angel were born, seven-year-old Nick walked into their nursery and freaked out, thinking: "Now I’ll have to be in charge of them too!"

The one saving grace for the Carters was when Nick started singing, after Jane heard him belting out 'Bridge Over Troubled Water’ at eight. Scraping together money for singing/dancing coaches and travel to auditions and shows, it became a family affair attending his performances.

He handed his first prize-check -- $100 -- to Robert and dreamed of earning enough that his parents would never fight again. But even when the checks he would later bring home were for millions, the turmoil continued.

It wasn't until Nick joined the Backstreet Boys at 12 that he saw what it was like to be part of a normal family. Through witnessing older members Brian Littrell and Kevin Richardson’s dedication to faith and family, he learned important values and principals, and was meanwhile welcomed into Howie Dorough’s large, close-knit clan.

However as the band shot to stardom, Nick stumbled into substance abuse, starting with booze in his teens then marijuana, cocaine and prescription painkillers. At the height of his problems, he downed a bottle of vodka with a side of cocaine and ecstasy every night and he believes the amount of ecstasy he took caused chemical changes in his brain, which now trigger bouts of depression.

"Anything from a bad fight with family or someone saying something about me will trigger my depression. Even eating badly -- hamburgers and fries -- it’s weird but the chemicals in my body won't process it properly and I get depressed."

"Through therapy I’m starting to understand those triggers so I can have more control."

Yet at the time of his drug-fuelled partying, no one and nothing could stop Nick. His bandmates attempted to help, but he continued on a downward spiral, which saw him arrested for drunk-driving in 2005, starting an unhealthy relationship with socialite Paris Hilton and starring in reality series "House of Carters," a well-meaning bid to bring his dysfunctional family together.

Moving into a Hollywood Hills home, Nick wanted to create the loving, family environment they never had growing up. His sisters were craving a taste of the celebrity life that he and Aaron had experienced, so he hoped the show would also offer them exposure, and a regular paycheck.

But still hooked on drugs and alcohol, Nick's hypocritical actions -- partying and hanging out with bad crowds yet discouraging his siblings from doing the same -- saw him lose credibility with Aaron, Angel, Leslie and BJ. Instead of uniting them, the show drove them further apart.

"If you saw more than five minutes of 'House of Carters,' first let me say, 'I'm sorry.' Secondly, screaming for my family is like casual conversation for most families."

The show wasn't renewed and after a wild all-nighter in Hollywood, Nick retreated to Tennessee where he rehabbed himself, assisted by the book "Why Some Positive Thinkers Get Powerful Results." It had been given to him on his 21st birthday by Kevin Richardson, but until then had been gathering dust.

Sadly, just a few months later, he was back on tour in Russia, downing "rivers of vodka" and competing with locals to see who could handle the most Sambuca shots.

Interview continues after video

His boozing continued and it wasn't until the Backstreet Boys took an unscheduled break following the death of Howie Dorough's father Hoke in June 2008, that Nick had the ultimate eye-opener.

Visiting his doctor for a check-up, he was diagnosed with cardiomyopathy, a potentially-fatal weakening of the heart muscle, in Nick's case caused by a build-up of toxins from drugs and alcohol.

The condition can cause sudden cardiac death, news which finally made him realize his actions had been like a suicide attempt.

He returned to Tennessee, surrounded himself with better friends and turned to fitness, replacing the high of drugs with the high of working out.

Today, he will "never touch drugs again," but confesses alcohol remains a struggle.

"It stems from years of alcohol abuse and it being in my family. But I love when I'm sober and clean much more than I like Party Nick, so I do everything I can to stay active and avoid situations where I could fall back into alcohol."

While the death of Leslie could have easily sparked a relapse, the loss has instead made Nick work harder to be a good role model for his family, and mend fences.

He has reconciled with Aaron, 25, the pair recently posting goofy photos together backstage at a Backstreet Boys concert. The brothers' relationship has been tumultuous, with Aaron following in Nick's footsteps both professionally, as a singer, and personally, with drugs.

In 2011, it was Nick and fiancée Lauren Kitt who took Aaron to rehab center Betty Ford to treat his addiction to Xanax (one of the drugs Leslie was reportedly also hooked on). While the pair are now on good terms, Nick confesses that some family relationships remain strained, including that with Leslie's husband Mike and their two-year-daughter Alyssa.

"It has been difficult. You get older and become tolerant of certain things and intolerant of others so I haven't been able to stay in touch with them. And with my parents, it's always a work in progress. We have to continue to go to therapy, stay open and talk. It's hard because there are outside influences, resentment, fear and mistrust. But we are talking."

Having started to make amends with loved ones, Nick is now preparing to commence his own family life with 30-year-old fitness expert and WBFF pro Lauren. The couple started dating almost five years ago and have proved to be positive, life-changing forces in each other's lives.

"Nick has inspired and motivated me," Lauren writes in a special note for his book. "His resilience and energy towards life are just a couple of his many admirable qualities that continue to transpire. I would not be the woman I am today if not for him and his unconditional love."

"We both come from imperfect backgrounds and have had many trials and tribulations," adds Nick, recalling when the pair met. "What I saw in her was a person who I wanted to protect, be with and who had a soft heart. She wasn't necessarily into the Backstreet Boys, but we clicked and knew we needed each other and could evolve together.

"She's someone who doesn't say 'Yes' just because. If I ask whether I had a good show, she'll say, 'It was good, but not the greatest.' She’s real with me. [When Leslie passed away] Lauren was my voice of reason. It was totally up to me not to attend the funeral and she supported me, held me and listened to me."

While dating a boy-bander isn't always easy and Lauren has copped nasty tweets from jealous fans, Nick hopes the pair's upcoming reality series -- tentatively titled "Getting Carter To 'I Do'" -- will help show the world their love.

He's well-aware that his last foray into reality television was disastrous, but believes people could learn from, and be entertained by, the man he has become. Once repelled by marriage, he's excited about settling down and hopes the lessons of his childhood will help him.

"I think I will be a dedicated, honest and faithful husband -- someone who will get it right where my family got it wrong. And when it comes to kids I’ll continue to work to be a better person and break the cycle -- not allow things that happened in my household to happen to my children."

Set to wed early next year, Nick's leaving the planning to Lauren: "I’m just going to show up!"

Meanwhile, bandmate AJ McLean is helping organize the bachelor party. All of his Backstreet brothers have played a part in Nick's recovery, but having shared similar paths, AJ couldn't be prouder.

"We've both struggled with drinking and drugs and when I was sober for a long period, he was really going through it," AJ tells Huffington Post. "He would ask my advice and he's my little baby brother so I'd never turn him away. What I tell anyone experiencing a rough patch is that the only way around is through. Unfortunately, some people don't make it out the other side but he did and I'm very proud.

"He's become such a strappy young man. He has grown and changed the most out of all of us, for the better. He's still a little pain in our ass - he always will be! But he's a smart kid with a good head on his shoulders and I'm happy he’s finally settling down."

While revelling in his personal and professional success -- including the ongoing Backstreet Boys 20th anniversary tour and his upcoming crowd-funded indie film "Evil Blessings -- Nick remains aware that overcoming alcoholism and depression will remain a challenge as he continues to strive to be a "happy, joyful, successful man” and someone whose family is “proud to share the same last name."

But he has clearly emerged from the dark tunnel that swallowed so much of his youth -- and hopes his book will help others do the same.

"I don't claim to be an expert -- I’m still learning. But I've been thrown many curveballs with family and addiction, so if someone can take something from my experiences to help their own life then I've given back.

"It's a resource people can turn to, so they don't have to suffer the pain I'm going through and experience the loss of a loved one. And so they can go, 'You know what? Maybe life's not as bad as it seems.' If I'd had the opportunity to give it to Leslie I think it would've opened her eyes and made a difference, and that's what I want -- to give someone else the chance she didn't get.

"No matter what relationship we had, she was my sister and I wanted the best for her. She's in a better place and I’ll always love her and my whole family. I want the best for all of them."