Demi Lovato. (Greatstock/Splash) Los Angeles - Demi Lovato thought she would be dead by the age of 21. The 23-year-old singer was admitted to rehab in 2010 for treatment for alcohol and drug abuse along with an eating disorder and self-harming and Demi thinks if she had gone on without seeking help she would not have survived. She told American Way magazine: "I lived fast and I was going to die young. She said: 'I was definitely like, 'Oh crap. In three years, that's going to be me.'"