Justin Bieber opens up about depression, drug use and 'insane pressure' of being a child star

In this Nov. 22, 2015 file photo, Justin Bieber arrives at the American Music Awards at the Microsoft Theater in Los Angeles. (Jordan Strauss/AP)

Pop star Justin Bieber says in a lengthy Instagram message that his struggles with depression and growing up as a child star led him to make “every bad decision you could have thought of” by the age of 20.

The 25-year-old singer also admits in the post Monday evening that he started doing “pretty heavy drugs” at 19 and “abused all of my relationships.”

Bieber, who is married to American model Hailey Baldwin, says he became distant to everyone who loved him and it took years to bounce back.

The "Sorry" singer opens up about his humble beginnings as the son of two teenage parents in Stratford, Ont., and how all that changed at the age of 13 when his musical talent progressed and he became “ultra successful.”

He says everyone did everything for him during his formative years, adding he never “learned the fundamentals of responsibility.”

Bieber credits his marriage who Baldwin, whose father is actor Stephen Baldwin, as helping establish more healthy habits.

“Luckily God blessed me with extraordinary people who love me for me,” he writes. “Now I am navigating the best season of my life: MARRIAGE!”

The pair wed in a courthouse ceremony last year and are planning a religious ceremony sometime this year.

“All this to say even when the odds are against you keep fighting,” Bieber writes.