Eilish also details how she came to the realization she doesn't "have any friends" while celebrating her 20th birthday.
Zoe Kravitz had a hard time getting to know the real Billie Eilish -- but it wasn't for a lack of trying.
In a new profile Rolling Stone magazine, the singer opened up about her reasons for cultivating a mysterious personality, something which led to her retreating from the public eye and isolating herself from others, including good friends.
"I'm afraid. For a f--king good reason. I'm afraid of people, I'm afraid of the world. It's just scary for somebody like me, and even if it's not scary, it means being on and being vulnerable and being seen and being filmed and whatever," Eilish, who has had stalkers show up at her home, told the publication.
"But with that all in mind, I have been choosing to do the thing that scares me more. I am biting the bullet and existing in the world for once," she shared.
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View Story"I had really scary things happen in my personal life and my safety was compromised a couple of times, and that's a big part of my life," Eilish continued. "That is something I just have to live with. But I don't know, it really made me resentful of my life, when you can't even be in your own house."
This feeling fed into her need to be an enigma and remain mysterious, which only brought isolation -- despite the public thinking she was "really cool."
"I used to be so obsessed with this mysteriousness, and I think that's 100 percent why I didn't make any friends, because I didn't want anyone to know me, because I wanted everyone to think of me as this mysterious, cool person," she said.
The now 22-year-old singer also recalled what Rolling Stone described as an "existential crisis" she had at her 20th birthday party.
"I looked around the room and every single person was an employee of mine," she told the publication. "I was like, 'Oh, s--t, I literally don't have friends. I don't have people that see me as an equal. I don't have people that aren't afraid of me.'"
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View StoryIt was around this time that Kravitz would often call Eilish to hang out. However, the singer would flake and never follow through with the catch ups.
Luckily for Eilish, Kravitz wasn't allowing for it and called Eilish out.
"I remember her being like, 'Why won't you hang out with me?'" Eilish recalled. "And I was like, 'Because when you get to know me, you're going to know me, and that's so terrifying to me, because then I'm not just, like, this person you think is cool. And what if you don't like me?'"
The singer/songwriter described herself as being "obsessed with the idea of being an anomaly" and remaining this "Billie Eilish character."
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View Story"Anyway, I have since thrown away that idea, and been hanging out with people. If they get to know me, that's OK. That's good."
Kravitz also spoke to the magazine about her friendship with Eilsh, saying she understood Eilish's initial reluctance to hang.
"We're both Sags [Sagittarius], so I totally understand the flightiness because I can be kind of similar," Kravitz said. "I think I probably just told her to shut up and get over it. And we've been really good friends ever since. It's actually the opposite of what she said: The more I get to know her, she gets better and better."
Eilish's profile in Rolling Stone magazine also details her experiences with depression, sexuality and her new album. Read the full interview here.