The first time Nikki McKibbin auditioned for "American Idol," she was drunk.

Luckily for her, she said the judges couldn't smell the three shots of tequila she downed in the hotel bar before she took a shot at fulfilling her childhood dream of singing stardom. But the pre-audition drinking was the beginning of a slippery slope that would eventually land the now-30-year-old Dallas native in a psych ward and on the upcoming second season of "Celebrity Rehab With Dr. Drew."

McKibbin said the barrage of harsh criticism she faced from notoriously caustic judge Simon Cowell [article id="1597303"]helped trigger a dangerous spiral of self-doubt[/article] that led to years of drug and alcohol abuse that she's just recently begun climbing out of. The singer, who charmed her way into the top three on the first season of "Idol" with her spunky rock attitude and flame-red hair, said she hit rock bottom last August when she stayed up doing cocaine and drinking with her mother, who died later that evening of a prescription-drug overdose.

"The worst time for me was when my mom died," McKibbin told MTV News, sounding on the verge of tears over the phone from her Dallas home. "I didn't have any control over myself at all, and I drank for nine months nonstop."

Growing up with a father she said was an alcoholic and drug addict in a home where she suffered from physical and sexual abuse from a family member, McKibbin said the trip to "Celebrity Rehab" was her first attempt at getting clean, and it's giving her a chance to talk about some deeply buried issues she's never been able to discuss before.

"I've always wanted to be able to talk about it to somebody who wasn't family who wouldn't get angry," she said of the abuse at the hands of a relative she prefers not to name. "I've tried therapy and psychiatrists, but what's different with ['Celebrity Rehab'] is that I needed to learn how to deal with this stuff. After I'd leave the psychiatrist's office, I'd go drinking because it was too painful to keep thinking about. When you deal with trauma as a child ... if you have an addict mentality and it's hardwired from the beginning, you don't know how to do anything else other than drink and take drugs to take the pain away."

McKibbin, who said she's been sober for 127 days, is not the first "Idol" alum to land on Drew's TV doorstep. The first season of the show featured troubled season-five finalist Jessica Sierra, who couldn't maintain her sobriety following her time with Drew and is currently in a one-year intensive treatment program after a [article id="1575599"]nasty run-in with police[/article] last year. McKibbin knows her road will be hard too, but she said she's committed to maintaining her sobriety, especially for her 10-year-old son and 13-year-old stepdaughter.

For McKibbin, alcohol was always the drug of choice, though she said before "Idol" she was hooked on the drug ecstasy for a time and following her run on the show, she would often do cocaine when she drank. In addition to auditioning drunk, while on "Idol," McKibbin, then 23, said she snuck a bottle of vodka into the downstairs refrigerator at the "Idol" house, which she shared with a number of other castmates of legal drinking age whom she preferred not to name. "There was nobody watching to make sure I wasn't drinking," she said. "And [when I auditioned drunk], my addict brain told me, 'That's what they get for doing auditions in a hotel with a bar,' " she said, adding that she never performed drunk on the show, if only because her schedule was so hectic.

With a ticking time bomb of addiction in her DNA, McKibbin said the spark that led to her downfall began with Cowell's withering comments about her singing. "For me, I had never been told I wasn't good," she said. "I'm by no means blaming him. I'm an addict, and if you tell an addict they're no good, it triggers you and makes you think you're worthless and useless and no good at the only thing you ever wanted to do your whole life."

Cowell's spokesperson, Lisa Dallos, told MTV News that she was attempting to get a comment from Cowell at press time.

"I was gracious on the show, and I held it together when I was on it, but when I got home, I was completely out of control," she said. "The drinking, the going out, especially at the beginning. Thinking I was the sh--, a rock star."

McKibbin said she never confronted Cowell about how his comments affected her -- and she now understands that he was just doing his job on a TV show -- but she recalled a fleeting encounter they had several years after "Idol" in an airport.

"He saw me holding this teddy bear and crying, and he said I looked like hell," she said with a hitch in her voice. "He had no idea what I'd been through. That teddy bear had been given to me from this girl who had cancer and was dying, and I had come down with the Make-A-Wish Foundation to see her. It was a really touching moment for me. He's been really hard on me, but I don't blame him. I think because I'm an addict, it hit a bit harder than with normal people."

Asked what she thinks Cowell would say now that she's told her story, McKibbin said, "I don't think he'd care. He's not interested enough in my life to give a sh--."

Looking back on her five-day stay in a mental ward last year after paramedics thought she was a danger to herself, McKibbin said she's working hard to maintain her sobriety and get her career back on track.

McKibbin released her debut album, Unleashed, on an indie label in 2007, after being dropped by RCA Records and 19 Management for spurning their suggestions to make a country album following her "Idol" run. She also had a short stint in the Dallas rock band Downside and a series of appearances on reality shows, including "Fear Factor," "Battle of the Network Reality Stars" and "Kill Reality." She's now working on her next album, which she said will be much "softer" and more emotional.

A handful of her new songs, including "From Here to There" and "Inconsolable," will debut on "Rehab," and she's been playing some local gigs with her new band, Wicked Attraction, while shopping for a record deal. She's also on the upcoming CD American Christmas, which features a number of fellow ex-"Idol" castmembers, including Jasmine Trias, Frenchie Davis, Ayla Brown, RJ Helton, Vonzell Solomon, Lindsey Cardinale and Haley Scarnato.

"I still have urges every day," she said. "I just have to learn to deal with them, and all I hope is that if someone sees my story, they'll be inspired to go out and get some help."

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