12/19/2017 12:48 EST | Updated 12/20/2017 09:34 EST

K-Pop Star Jonghyun’s Death Reveals Heartbreaking Reality Of Life In The Limelight

The lead singer of SHINee battled depression.

The sudden death of one of South Korea's biggest pop stars is shedding light on the heartbreaking reality of how fame can take a toll on mental health.

Kim Jong-hyun, known by his stage name Jonghyun, was the lead singer of the popular K-pop boy band, SHINee. On Monday evening, the 27-year-old was found unconscious in an apartment in Seoul and rushed to hospital where he was pronounced dead.

Investigators said they believe the singer died from inhaling toxic fumes, and police released an official statement to Soompi on Tuesday ruling Jonghyun's death as a suicide.

One day after the singer's death, Jonghyun's close friend Nine9, who is a member of the K-pop group Dear Cloud, shared a farewell note Jonghyun had written.

The letter, which was reportedly handed to Nine9 two weeks before the singer's death, revealed heartbreaking details of his battle with depression.

"I was broken from the inside," he wrote. "I suffered and agonized about it. I never learned how to turn this pain into happiness. The depression that was slowly devouring me at last consumed me."

Jonghyun also wrote about the pressures of being a celebrity. "The life of fame was never meant for me," he said. "Everyone just lives just because. If you ask why people die, they would probably say it's because they're exhausted."

The Korean entertainment industry is known for its high pressure, non-stop work culture, Variety reports. Because of the unhealthy demands placed on Korean celebrities, both mentally and physically, many famous figures have taken their own lives, such as singer Seo Ji-won, who died in 1994 at age 19, and actress-turned-singer U;Nee, who died in 2007 at age 26.

Variety notes that many Korean celebrities who died by suicide left similar notes criticizing the high pressures of the country's entertainment industry and detailing their own struggles with depression.

Now some fans are hoping Jonghyun's sudden death will serve as a "wake-up call" not only to the industry, but also to the country who needs to start openly addressing mental health.

"In Korea, there is no such thing as mental health," Jin-Hee, a Korean-American mental health professional, told Forefront Suicide Prevention earlier this year.

"One is seen as 'weak' if they have a mental health issue. People with mental health issues are seen as 'crazy' and the issue is something that must be overcome."

This is evident in Jonghyun's case, as his goodbye letter noted how his doctor "blamed his personality for his inability to shake off the depression," resulting in him believing he was not cut out for life in the limelight.

In addition to shedding light on mental health, other fans are hoping Jonghyun's death will also remind people that K-pop stars (and celebrities in general) are human too.

It is not uncommon for celebrities to suffer mental health problems outside of the Korean entertainment industry. In Hollywood, Robin Williams took his own life in 2014, and most recently Linkin Park's Chester Bennington died by suicide in July.

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