Elton John
He was legendary on stage but behind the curtains, Elton John was really shy. He turned to drug abuse in order to cope with his shyness, but that led to more dangerous issues. In a 2010 interview he admitted that his day to day life meant staying awake for days, indulging in cocaine and alcohol abuse, and binge-eating that later led to bulimia.
He also experienced near-death experience due to substance abuse. He would have seizures and then he would keep consuming drugs.
His path to sobriety started with the help of a teenager that was infected with HIV. Seeing him die became a wake-up call for Elton John and he has been sober since.