Halsey's new song is her most vulnerable yet.

The 29-year-old released "The End" from her upcoming fifth studio album, and with it she's shared some details about a previously private health struggle she's been experiencing for the last few years. 

"Long story short, i'm Lucky to be alive," she captioned a June 4 Instagram. "Short story long, i wrote an album. It begins with The End. Out now."

And though Halsey didn't outright name the health issues she's been dealing with, she tagged the Lupus Research Alliance as well as the Leukemia & Lymphoma Society within the caption. 

The post itself featured a carousel of images and videos, including an emotional montage of herself receiving medications via IV as well as clips of her crying, a second where she tells the camera, "Today is day one of treatment," a screenshot of a Notes app titled "The end of the f--king world" sent to a friend in 2022, a clip of her in a recording studio as well as a clip in which she rubs speaks to someone off camera, a bandage around her elbow.

"Seriously, like an old lady," she says in the clip, while rubbing her legs. "I told myself I'm giving myself two more years to be sick. At 30 I'm having a rebirth and I'm not gonna be sick, and I'm going to look super hot, and have lots of energy, and I'm just going to get to redo my twenties in my thirties." 

The Grammy nominee's post was soon full of well wishes, including a message from one user that read, "YOU'RE SO STRONG," and another who added, "I love you. Chronic illness is hell but you're incredible."

And while Halsey may have kept the specifics of her diagnoses and treatment private, "The End" does provide an intimate look into her struggles.

"Every couple of years now, a doctor says I'm sick," she sings in the song's opening line. "And at first, it was my brain, then a skeleton in pain / And I don't like to complain, but I'm saying sorry."

Halsey—who confirmed her relationship with Avan Jogia in October—then continues, "When I met you, I thought I was damaged goods / Had a f--ked up childhood / And there's poison in my brain and in my blood."

"When I met you, I said I would never die / But the joke was always mine 'cause I'm racing against time," she sings in the final verse. "And I know it's not the end of the world, but could you pick me up at 8? / 'Cause my treatment starts today."

Halsey's emotional song and health news come shortly after she fiercely defended Kate Middleton amid the scrutiny on the Princess of Wales' retreat from the public eye, which she eventually shared in March was due to a cancer diagnosis. 

"Hope the people and the media who sensationalized a woman's desire for privacy following a known health incident are experiencing regret and remorse," Halsey wrote in an Instagram Story March 23. "And by the way, that would stand even without the terrible news of her journey."

The "Without Me" singer also expressed her belief that even those living in the spotlight are entitled to their privacy. 

"I understand when you have a public life certain things like this can get out of hand," she continued. "But god forbid someone needs a break for a few weeks or months, it's no one's business why. And with respect to public life, who you are and how you're doing when you ‘sign up for this' is subject to change at any moment. And the newly changed ‘you' in place (for whatever amount of time; days weeks years) may not have the same stamina or tolerance." 

Kate's video message sharing her diagnosis noted part of the reason her family kept the news private at first was so she and Prince William had time to tell their kids Prince George, 10, Princess Charlotte, 8, and Prince Louis, 5—a sentiment Halsey, who is mom to son Ender Ridley Aydin, 2, with ex Alev Aydin, could likely resonate with. 

For some of Halsey and Ender's sweetest moments together, keep reading. 

Halsey gave her son Ender—who she shares with Alev Aydin—a boost up in this April 2023 snapshot.

The mother-and-son duo warmed up with a hot drink—and a cozy snuggle!—while celebrating the holiday season in November 2023.

Halsey gave a glimpse inside her mornings as a mom in April 2022, writing on Instagram, "pockets of happy to get me through."

The singer held her son close while vacationing in France in June 2023.

"I guess no matter what your parents do, it’s cooler to like whatever’s the complete opposite," Halsey wrote on Instagram April 2023. "I love my monster truck kid."

Halsey and Ender ran down the sidewalk together during a visit to the farmer's market in September 2023.

Nursing is all in a day's work for the About Face founder. Or as she put it in the caption of this August 2021 photo: "welcome to the jungle."

Ender adorably strummed a guitar as his mom watched in this November 2023 snap.

Halsey celebrated Ender's six-month birthday in January 2022 with a painting party.

"he sorta just looks like the club kid Pope though," she quipped on Instagram. "they said it would go by fast but sheeeeeesh."

Halsey captioned this sunset snap, "sweet life."

"#worldbreastfeedingweek," Halsey wrote on Insatgram in August 2021. "we arrived just in time!"

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