The singer's Jan. 4 remarks came at the Palm Springs International Film Festival, where she and O'Connell became the first musicians to ever receive the chairman's award.
"I would really like to say that this award and any recognition that this song gets, I just want to dedicate to anyone who experiences hopelessness, the feeling of existential dread and feeling like, what’s the point, why am I here and why am I doing this?" Eilish said while standing on the podium, as transcribed by the Hollywood Reporter.
"I think we all feel like that occasionally, but I think if somebody like me, with the amount of privilege that I have and the incredible things that I get to do and be and how I have really not wanted to be here…sorry to be dark, damn, but I’ve spent a lot of time feeling that way."
Eilish had some words of encouragement for others struggling with mental health issues.
"I just want to say to anyone that feels that way, be patient with yourself and know that it is, I think, worth it all," she said.
Eilish added that working on Barbie helped pull her out of a negative headspace.
Before the film she "was in a dark episode and things didn’t make sense in life. I just didn’t understand what the point was and why you would keep going. [I was] questioning everything in the world."
That started to change after director Greta Gerwig showed Eilish and O'Connell 35 minutes of footage from the movie.
"Basically I was just watching Barbie say and feel things that I really, really, really resonated with and felt so close to. I felt so seen, and I did not expect that," the singer said. "I think that this movie is the most incredible, most empowering and beautiful and funny and just unbelievable piece of art in the world, and I’m so honored to be a part of it."
Eilish then turned the mic over to O'Connell, who thanked his parents and told the story of how the couple met.
"Our parents were theater people before they were our parents. They met on a flight to Alaska to do regional theater in 1984, and in the '90s they got married to each other and decided to start a family. They decided that it might be a good idea to move from New York where they were doing plays to Los Angeles to maybe do some things that would make some residual income like film and television," he said.
"That didn’t work out at all, and I think it underscored as children that it was okay to have dreams that didn’t pan out the way that you thought they might. And it also underscored that the entertainment industry, like all industries, is fairly unfair."
O'Connell added that his folks weren't bitter about their poor fortunes in the entertainment industry and still encouraged him and Eilish to pursue their music dreams.
Last month, he revealed that Eilish's third studio album is "85% done."