It was something out of a fairy tale, if everyone in fairy tales wore denim and leather and looked like they smoked American Spirits. One minute, Olivia Jean was a shy kid from Michigan competing in her school’s battle of the bands show, and the next, she’s performing with her boyfriend, the musician Jack White, and he’s proposing to her in the middle of his song “Hotel Yorba” — right before the line “Let’s get married/ In a big cathedral by a priest.” A minute later, Mr. White remembered, come to think of it, one of the guys backstage was a licensed minister — does she want to get married right then?

She said yes.

On an early April evening, a crowd that had gathered in the Masonic Temple of Detroit for the kickoff of Mr. White Supply Chain Issues tour was drenched in the warm glow of love, bright blue stage lights and a couple of contraband cellphones that enterprising audience members had managed to slip past security. Also in attendance: the father of the bride, Brent Markel, who had been watching the show, unaware of what was to come, and appeared onstage to give his blessing.

“Initially I was shocked and confused when Jack said, ‘Let’s get married right now,’” Mr. Markel said. “But when I realized it was happening, I was so happy for them.”

Altogether, Ms. Jean and Mr. White’s entire marital courtship — engagement to wedding — lasted just five and half minutes.

“It was the best experience of my life,” Ms. Jean, 32, said several weeks later. “You could plan a wedding for five years and it wouldn’t compare to that.”

At her favorite vintage store in Nashville, where the couple live, Ms. White showed off her appropriately goth engagement ring: a marquise cut onyx that she had worn on her middle finger for years, and that Mr. White, 46, surreptitiously had customized while under the guise of getting it cleaned. He had three black diamonds added on either side, and a small diamond placed in the middle. “It looks like a spaceship,” Ms. Jean said, admiring her pale, slender hand. “Or a beetle.”

Ms. Jean floated through the racks of cat T-shirts and whimsical sweaters with a surprising lightness for someone with combat boots the size of compact sedans strapped to her feet. Her look is that of a rockabilly Morticia Addams: long, jet black hair, severe bangs over glacier blue eyes and swooping eyeliner sharp enough to cut glass.

Marriage stories have a way of eclipsing everything around them, especially for women, and especially for women marrying a mega-celebrity, like Ms. Jean just did.

Take June Carter Cash’s ambivalence toward her own onstage engagement — the less goth predecessor of Mr. White and Ms. Jean’s nuptials. In 1968, Johnny Cash proposed to Ms. Carter in front of a crowd of 7,000 people in London, Ontario. When asked about the engagement 13 years later, in a joint 1981 interview on the “Mike Douglas Show,” Ms. Cash said: “You’re not going to make me tell it again!”

Ms. Jean has not yet tired of her own engagement story, but she said that long before Mr. White placed the beetle ring on her finger, she was a musician with her own body of work and her own fans. She performed with the band the Black Belles from 2009 to 2012, then released two solo albums, “Bathtub Love Killings,” in 2014, and “Night Owl,” in 2019. During the pandemic, she started working on a third album, which is mostly done, but probably won’t be released until 2023 because of a vinyl shortage.

Ms. Jean’s music is loud and muscular, a distinctly Americana combination of brash garage rock and boppy surf music. It’s music to listen to while applying red lipstick in the rearview mirror of a convertible, or while fantasizing about smashing an ex’s TV with a baseball bat.

What she writes about best, she said, is “frustration, stress and being angry,” though she insists that in reality she’s really quite content. “I live a pretty easygoing, happy life,” she said, smiling. “That just seems to be the only thing that inspires me, is writing about sassy emotions.”

The wedding did change things, though. There’s being a successful musician, and then there’s being a successful musician whose spontaneous wedding to a well-known rock star made headlines around the world.

Fans know rock star couples on a first-name basis: Sonny and Cher; John and Yoko; Whitney and Bobby. These couples become greater than the sum of their two parts. Fairly or not, their art and their relationships become inextricable, each one seeming to fuel the other — the romance inspires the music, and the music inspires grand, romantic gestures, like, say, getting married onstage in front of thousands of people.

“I feel like a spotlight’s been put on me after that experience,” Ms. Jean said. “It was a really positive thing that happened, and it makes me happy to know that other people approve of it, and appreciate how cool that was. So it’s positive, but strange. Very strange.”

Ms. Jean grew up in the suburbs just outside of Detroit. Her parents encouraged their four children to be creative.

When she was 7, inspired by a B-52’s record she stole from her father, Ms. Jean got her first guitar and started teaching herself to play. In second grade, she formed a band called Broken Glass. At 12, she started a band with her brother. They played the school talent show and won the battle of the bands, a victory that still clearly delights her.

By high school, Ms. Jean was a loner who spent much of her free time recording her own surf music. She played all the instruments herself, recording each on a tiny computer microphone and layering them on top of each other with a free audio editing program. At 16, she started playing small clubs around Detroit. She handed out her homemade CDs to friends and co-workers, who mostly seemed confused by the offering. “It was a hobby,” she said. “I didn’t know you could make money off of music.”

Then, in 2009, when she was 19 and going to school for graphic design, Ms. Jean had two very important conversations in quick succession. The first was with a friend, who told her that the Dead Weather, Jack White’s band, was playing a secret show in Detroit that same night. She had two hours to grab a stack of her demos of instrumental surf music and rush to the venue, where she scattered the CDs on tables and chairs.

But the people in the audience weren’t the ones whose attention she really wanted. Slipping outside, she laid out a path of demos from the band’s tour bus to the side door they used to enter the venue — a yellow brick road of rock music.

The second very important conversation was with Mr. White, who called her a couple of weeks later and said that he liked her music, and asked her if she wanted to come to Nashville and record some of her songs with him at his recording company, Third Man Records.

“I put the phone down and then I just laid on the ground for a few minutes,” Ms. Jean said. “Like, this is not real. This can’t be real. This doesn’t happen to people.”

Mr. White, who had watched with his band as Ms. Jean laid out the CDs in front of their bus, remembered being floored by her demo when he heard it.

“The fact that she incorporated surf guitar and the low-fi recording of all the instruments (that she played herself) into her songs, while also being from Detroit, not to mention the bouffant hairdo and style, all showed me this was a very unique and talented person worth inviting into the Third Man world,” he wrote over email.

It was the moment all aspiring rockers dream of when they hang up posters of their favorite bands on their bedroom walls. But Nashville can be humbling, even for the most talented amateur musician. In Music City, music isn’t a hobby, it’s a career. As Ms. Jean put it: “I thought I was awesome in Detroit, and then I moved here.”

Ms. Jean dropped out of school and started recording music for Third Man. In Tennessee, she met Ruby Rogers and Shelby Lynn, a pair of musicians with whom she clicked, partly because they shared that most sacred of human connections: similar hairstyles. The women formed a band, the Black Belles, and started recording some of Ms. Jean’s songs. They performed together for three years and gained a decent amount of attention. They put out a record that Mr. White produced and collaborated on songs with the actress Elvira and the late night host Stephen Colbert.

“It was hard in a good way, because it inspired me to become better,” Ms. Jean said of that period. “But at the same time, you become a little less confident in yourself. You start to realize, I’m not as great as I thought I was, so now I really need to work.”

Over email, Ms. Rogers recalled “rehearsing constantly,” and Ms. Lynn wrote that “The Black Belles was a crash-course in rock ’n’ roll.”

“It was an absolute whirlwind of blood, sweat and mascara-drenched tears,” Ms. Lynn said. “We grew up together in those years, and the creative bond we developed, it became almost telepathic and has been unmatched in any other band setting I’ve found myself in. It was high pressure to be sure, and I think that brought out our finest work as musicians.”

In 2012, the Black Belles split amicably. Ms. Jean took a couple of years off. Eventually, in 2014, she put out her first solo album.

It was around that time that her relationship with Mr. White evolved into something more serious. “We were just really good friends,” she said. “You have to know that you can be friends for a while before you can date. It wasn’t really a transition. It was more, OK, this is happening. More like a continuation.”

During the pandemic, the couple hunkered down at their Nashville home, and according to Ms. Jean “tried to be as creative as possible.” They both worked on their music, and Mr. White helped produce Ms. Jean’s new album. She also worked on various graphic design projects for Third Man as well as her own merchandise. The creativity was so overflowing in their house that it got a little crowded. Ms. Jean decided to convert the pool house into her own music studio so that she and Mr. White wouldn’t be competing for time in his. She painted the walls hot pink and covered the floors in plush, hot pink carpet.

“My little pink nightmare,” she said.

So far, she said, it hasn’t even really hit her that she’s married. No sooner did they get hitched than Mr. White went off on tour, and she’s mostly been back in Nashville, putting the finishing touches on her new record and rehearsing with her band.

“I’ve realized as I get older that I have my own thing. I’m niche,” she said. “This is who I am, and people accept that or they don’t, it doesn’t matter to me.”