From her 2001 breakdown to Glitter: The highs and lows of Mariah Carey's career.

Mariah Carey is the first artist to top the Billboard Hot 100 in four separate decades, because of course she is.

Her Christmas banger All I Want For Christmas Is You will top the chart dated January 4, 2020, following two previous weeks in the top spot.

And it was originally released in 1994.

I mean. You know the song, but… Post continues below video. 

All I Want For Christmas Is You became Mariah’s 19th number one, after she earned 14 in the 1990s and four in the 2000s.

And well, she celebrated her new record like only Mariah can.

Yaaaaaaaaay!!! WE. DID. IT. ????????????????????????????
But…. what’s a decade? https://t.co/OaNK23GFuN

— Mariah Carey (@MariahCarey) December 30, 2019

Celebrating on the move! ???????????? pic.twitter.com/rhgQSh8P03

— Mariah Carey (@MariahCarey) December 30, 2019

It’s a new high for Mariah’s career. She’s one of the highest selling artists of all time, with a net worth of more than AU$428 million and a rare five-octave vocal range.

She’s undoubtedly iconic, but her career hasn’t always been full of success.

Mariah Carey was born in Huntington, New York in 1969 or 1970 (not even the internet knows). Her mother Patricia was a voice coach and opera singer, who almost immediately realised how talented her daughter was.

In 1988, the head of Columbia Records Tommy Mottola got his hands on Mariah’s unnamed demo and spent two weeks tracking her down.

Her debut self-titled album was released in June 1990. Her first four singles Vision of Love, Love Takes Time, Someday and I Don’t Wanna Cry all hit number one on the charts making Mariah the first artist since The Jackson 5 to have their first four singles top the charts.

She also won two Grammys and oh, sold 15 million copies in 1991 alone.

Her second album Emotions was released in late 1991, but didn't sell as well as her debut (still, 8 million copies is not bad).

She released Music Box, her third album, in 1993. Just before its release, Mariah married Tommy Mottola.

In 1994 Mariah released that Christmas album. Mariah filmed her and Tommy's Christmas for All I Want For Christmas' primary music video, which features grainy home-movie footage of Mariah and her family.

At the time of her marriage to Tommy, Mariah was 23 and he was 44. Speaking to Cosmopolitan in July 2019, Mariah stated: "You might want to picture a child bride."

"There was a conscious effort to keep me as this all-American, whatever that means, girl. It was very ­controlled. There was no ­freedom for me as a human being. It was almost like being a prisoner," she said.

Tommy has also called the relationship "wrong and inappropriate," and they split after eight years.

After the breakup, Mariah hit the social scene. She was romantically linked to Diddy and baseball player Derek Jeter, but her next serious relationship was with Mexican singer Luis Miguel.

They split in 2001, around the same time that Mariah suffered a physical and emotional breakdown.

On July 19, 2001, Mariah made a surprise appearance on the MTV program Total Request Live (TRL). The appearance was erratic, and she shocked viewers by stripping down to a green shirt and yellow shorts.

Afterwards, Mariah posted messages on her website that complained of being overworked.

"I'm trying to understand things in life right now and so I really don't feel that I should be doing music right now. What I'd like to do is just a take a little break or at least get one night of sleep without someone popping up about a video. All I really want is [to] just be me and that's what I should have done in the first place ... I don't say this much but guess what, I don't take care of myself," she wrote.

A week later, she was hospitalised after her mum found her in a hotel room bleeding from cuts.

Her publicist Cindi Berger said the star had experienced an "emotional and physical breakdown" but denied tabloid claims she’d tried to take her own life.

"She did break some dishes and glasses, and she may have stepped on them," Berger's statement said.

Mariah spent two weeks recovering in an undisclosed facility in Connecticut, but her troubles weren’t over.

Two months later, in September 2001, Glitter, a film staring Mariah and based on her life was released and universally panned. The soundtrack, also titled Glitter, became her lowest selling album.

Mariah contributed some of its failure on its unfortunate release date: The album came out on September 11, 2001 and the movie 10 days later.

Even now she's not particularly keen on talking about Glitter, telling Jimmy Fallon in November 2018 that it "almost ruined my life."

Her next two albums Charmbracelet and The Emancipation Of Mimi re-established Mariah as a chart topper.

In 2008 she met comedian Nick Cannon on the set of her music video Bye Bye and after just six weeks, they married in the Bahamas.

In 2009 Mariah's performance in Oscar-winning film Precious was critically acclaimed, and on her and Nick's third wedding anniversary in 2011 she gave birth to twins Moroccan and Monroe.

For a while, she had the stable family life she'd craved. Her parents divorced when she was three, her father died in 2006 and she was estranged from her two siblings.

She joined the American Idol judging panel in 2013, but only lasted one season. She butted heads with fellow judge Nicki Minaj, and told Hot 97’s Angie Martinez that she "hated it."

"I thought it was going to be a three-person panel," she said. "But it wasn't that."

"It was like going to work every day in hell with Satan."

In August 2014, Nick and Mariah confirmed their separation. Nick filed for divorce in December and it was finalised in 2016.

The relationship breakup coincided with another period of career lows for Mariah.

Her 2014 album Me. I Am Mariah... The Elusive Chanteuse flopped.

She held a Las Vegas residency from 2015-2017, performing all of her 18 of her No. 1 singles in chronological order.

In October 2016 she split from billionaire fiance James Packer, who she had been dating for over a year.

On December 4, 2016, her reality show Mariah's World premiered on E!. It received negative reviews and was not picked up for a second season.

On New Year's Eve that year, her performance on Dick Clark's New Year's Rockin' Eve in Times Square received worldwide attention after technical difficulties caused Mariah's in-ear monitors to malfunction, resulting in what The New York Times referred to as a "performance train wreck."

But three years on, Mariah is back on a high.

She has been dating dancer Bryan Tanaka since 2016 and is enjoying keeping her private life a little more, well, private.

"I don’t really talk about my personal life," she told the Associated Press in 2017.

"Because that’s what I used to do and it really worked for a minute back, a while ago. I just don’t feel comfortable talking about my personal life … me and my boyfriend don’t want to do that."

In April 2018 she told PEOPLE she had been diagnosed with bipolar II disorder when she was hospitalised in 2001.

"I didn’t want to believe it," she said, saying she had recently received treatment after "the hardest couple of years I've been through."

"Until recently I lived in denial and isolation and in constant fear someone would expose me.

"It was too heavy a burden to carry and I simply couldn’t do that anymore. I sought and received treatment, I put positive people around me and I got back to doing what I love - writing songs and making music."

She and Nick also happily co-parent their twins, who are now eight.

Plus no matter the career lows, Mariah can always count of December to lift her up.

After all, she has the most successful Christmas song of all time.