'American Idol' star Justin Guarini endured dark spiral after Hollywood dream collapsed

At the start of his career, Justin Guarini seemed to have it all: fame, fortune and a promising future in Hollywood.

After becoming the runner-up on the first season of "American Idol" in 2002, Guarini was thrust into the spotlight seemingly overnight. But when his Hollywood dream came crashing down, he found himself in a dark place that he would eventually come to view as one of his greatest blessings.

"I think it was one of the greatest things that could ever have happened to me," Guarini, who recently released his book, "Center Stage Confidence: How to Own Your Story and Command Any Room," told Fox News Digital. "Failure is the greatest teacher, one of the greatest teachers that we can have in any given situation because in that failure, you have one of two paths. You either give up or you keep going."

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However, this mindset didn't sink in until much later.

In his book, Guarini recalled the moment he learned he had been dropped by his record label, RCA, in 2003.

"I stared at the TV in shock as my entire world came crumbling down around my ears," Guarini, who said he learned the news during a "Weekend Update" segment on "Saturday Night Live," wrote in his book. "Every illusion of fame, fortune, and glory fell away in an instant — only to be replaced by the silence of loss. In that moment, the veil of my arrogance, my assumptions, and my entitlement were lifted away, and I saw my life for what it had become."

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"I spent months playing my sad story on repeat," he added. "I lost weight, slept more and more, and became less and less like myself, and the people who loved me started to notice and worry. I was living the ghost of the life I had always dreamed of and burning money and time in equal and absurd measure."

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As the first runner-up in "Idol" history, Guarini believed his future in the entertainment industry was secure. But his early success proved difficult to sustain.

In 2003, he released his self-titled debut album and starred alongside Kelly Clarkson in the musical romantic comedy "From Justin to Kelly." While his album debuted in the top 20 on the Billboard 200 chart, the movie flopped, and criticism of his performance and appearance continued.

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As his career stalled, Guarini struggled to reconcile his newfound reality with the life he had envisioned.

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