Sinead O'Connor says infamous 'SNL' performance is still her 'proudest' moment in new documentary

Sinead O'Connor gets to have her say in a new documentary.

"Nothing Compares," which premiered virtually at Sundance Film Festival late Friday night, heartbreakingly recounts the Irish singer's life from her abusive childhood to her infamous 1992 "Saturday Night Live" performance, which either torpedoed or immortalized her career, depending on who you ask.

The film's bow comes less than a week after O'Connor worried fans with a series of upsetting posts on social media regarding the recent suicide of her 17-year-old son, Shane. The artist has not given interviews or promoted the film this past week, nor does she appear on screen throughout it, with the exception of archival footage.

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But O'Connor, 55, is occasionally heard in voiceover during "Nothing Compares," with reflections on fame and public scrutiny that take on stirring new poignance in light of recent events.

"They broke my heart and they killed me, but I didn’t die," she says. "They tried to bury me. They didn’t realize I was a seed."

O'Connor's voiceovers are the most revealing parts of the documentary, which traces her career beginnings but curiously ends with the fallout from her "SNL" performance, in which she tore up a picture of Pope John Paul II while singing Bob Marley's "War," in protest of child sex abuse in the Catholic Church. (O'Connor has released seven albums since 1992. An end credits coda states that she has more music in the works.)

"I did suffer through a lot," she says at the start of the film. "Everyone felt it was OK to kick the (expletive) out of me. I regret that I was so sad because of it," adding that she spent many years feeling "very isolated and lonely."

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The film details O'Connor's religious upbringing and alleged abuse by her mother, Marie. In one particularly harrowing section of the film, she describes how her mom locked her outside and forced her to sleep in the garden, even as she stood by the window and begged to be let back inside. Marie later died in a car accident when O'Connor was just 19.

The artist later reveals that she thinks of her mom and "the little girl in the garden" whenever she sings "Nothing Compares 2 U," her emotional Prince-penned ballad that spent four weeks at No. 1 in 1990. She also says that she never cried while recording the song, but couldn't help herself while shooting its stark music video, in which she stares directly into the camera.

O'Connor repeatedly comes back to the idea of music as therapy, saying how she never wanted to be a pop star but simply wanted to "scream." Old footage shows her cheekily responding to journalists' inane questions about her shaved hair and seething "rage," despite her hushed voice and petite figure. ("I don't know, perhaps there's something twisted about me that I haven't realized yet.")

The film's climax shows O'Connor performing at Madison Square Garden during an all-star tribute to Bob Dylan, less than two weeks after she tore up the photo of the pope on "SNL." The singer was set to cover Dylan's "I Believe in You," but decided to once again perform "War" after she was met with a mix of cheers and boos from the audience.

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"It's the weirdest noise I've ever heard in my life. It makes me want to puke," O'Connor says later, reiterating that she has "absolutely no regrets" about her controversial "SNL" performance. She even says it's the "proudest" thing she's ever done as an artist.

"I regret that people treated me like (expletive)," O'Connor says in voiceover. "And I regret that I was so wounded already that that really, really killed me and hurt me. They all thought I should be made a mockery of for throwing my career down the drain. I didn’t say I wanted to be a pop star. It didn’t suit me to be a pop star. So I didn’t throw away any career that I wanted. It didn’t change my attitude."

National Alliance on Mental Illness (NAMI) HelpLine: 1-800-950-NAMI (6264) or info@nami.org; available Monday through Friday, 10 a.m. to 6 p.m. ET for information, resource referrals and emotional support.

National Suicide Prevention Lifeline: 1-800-273-8255; available 24/7 for support, prevention and resources.

Crisis Text Line: Text HOME to 741741; available 24/7 for crisis counseling.

This article originally appeared on USA TODAY: Sinead O'Connor talks regret, abuse in Sundance doc 'Nothing Compares'