The 'Born This Way' singer admitted that she used to take cocaine to help her cope with loneliness.
According to Rolling Stone, GaGa opened up about the depression she suffered at the age of 19 during an interview on US show The Conversation with Amanda de Cadenet.
"I would go back to my apartment every day and I would just sit there," she revealed. "It was quiet and it was lonely. It was still. It was just my piano and myself. I had a television and I would leave it on all the time just to feel somebody was hanging out with me."
She went on to describe the way she used cocaine to "fill the void", saying: "It was like the drug was my friend. I never did it with other people. It's such a terrible way to fill that void, because it just adds to that void, because it's not real.
"I sort of f**king woke up one day and was like, 'You're an asshole. You're not an artist.'
"If you were a real f**king artist, you'd be focused on your music. You wouldn't be spending your money on the white devil."
GaGa has previously described her past drug use as "traumatic".
It was reported earlier this week that GaGa has split with alleged boyfriend Taylor Kinney.
Tickets for Lady GaGa's 'Born This Way Ball' UK tour are now available here.
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