What’s wrong with Madonna?

Insiders say her bizarre, Norma Desmond-like “Quarantine Diaries” on Instagram, coming on the heels of her recent disastrous “Madame X” concert tour, are proof the 61-year-old star has lost touch with her audience.

“I worshipped her, we all did,” said someone who has worked with Madonna in recent years and has ties to her inner circle. “I still do, but I’m disappointed. It’s like she’s selling out to keep getting attention and she doesn’t know how weird she’s coming off. I keep hoping she’ll snap out of it.”

Her “Quarantine Diaries” show the icon at a typewriter late at night, mumbling about her existential and physical angst. In one, Madonna shows a close-up of a gummy-bear edible she uses to ward off her hip and knee pain. She also said she misses “interacting with people” and often cannot sleep. In another, she says she’s lost three friends “in the last 24 hours” though it’s not clear if they died of COVID-19.

Meanwhile, a video she posted of herself naked in a bathtub and calling the virus “the great equalizer” was deleted after blowback about her wealth and privilege.

Some of what Madonna posts online is fun, like videos of her singing with son ­David, 14, or snippets of her 8-year-old twin daughters, Estere and Stella, working out with Madonna’s Bronx-born personal trainer Marlyn Ortiz. But then there was the cringeworthy one of her singing “Vogue” into a hairbrush with lyrics about fried fish.

Even a longtime fan, nightlife columnist Michael Musto, told The Post it was “one of the worst things I’ve ever seen.”

Howard Stern grilled Rosie O’Donnell about her friend Madonna last week, referencing the “milk bath” video and asking if Rosie can ever “be honest” with Madonna and tell her she’s coming off badly. Rosie said yes, but Madonna “won’t listen.”

Representatives for the singer did not return requests for comment.

Sources say Madonna lost a savvy guiding hand when her longtime publicist, Liz Rosenberg, retired in 2015.

“No one around her today can tell her anything,” said Brad Jeffries, who choreographed for Madonna for years, including the “Like a Virgin” tour, and was also friends with Rosenberg. “Liz could, but she’s gone. That’s why [Madonna] seems to be going so deep into the crazy right now. I defend her right to sleep with 25-year-olds because if she were a 61-year-old guy sleeping with 25-year-old women no one would blink an eye. But the way she’s doing it comes off a little desperate.”

Madonna has often gone out with younger men but since her 2008 divorce from her second husband, British film director Guy Ritchie, 51, she’s become a serial cougar.

She began dating then-21-year-old model Jesus Luz — a Brazilian 28 years her junior — after her split from Ritchie and was with him for two years. She made it publicly known that sex with Luz “was the best I ever had.”

French dancer Brahim Zaibat, also 28 years younger than Madonna, came next. After that was Dutch dancer Timor Steffens (29 years younger), then model Aboubakar Soumahoro (32 years younger) from the Ivory Coast in 2016. Last December she went public with her latest boy toy — 25-year-old backup dancer Ahlamalik Williams, from the Sacramento, Calif., area — whose father has said is “very serious” with Madonna.

Insiders say it’s a rebellious backlash in response to her eight-year marriage to Ritchie, with whom she shares sons Rocco, 19, and David. (Madonna also has a 14-year-old daughter, Mercy — who, like David and the twins, is adopted from Malawi, Africa — and 23-year-old Lourdes, whose father is fitness trainer Carlos Leon.)

During her years with Ritchie, Madonna seemingly settled down: moving to the English countryside and adopting a British accent, writing children’s books and sporting a more subdued style.

It was all antithetical to the wild child who had torn through downtown Manhattan with Jean-Michel Basquiat, offended the world with her “Like a Prayer” video and “Sex” book, made out with Britney Spears and tossed the F-bomb at David Letterman on air.

“Guy Ritchie broke her,” said a former member of the Kabbalah Centre who has known Madonna for decades. “He wouldn’t take any crap from her and she couldn’t handle it. He was the last of her alpha males.”

Besides, the Kabbalah source added: “Frankly, most guys her age who she would want, [they] want 25-year-olds themselves.”

Her split with Ritchie has lingered, first in the form of a custody battle over Rocco in 2015 and, as recently as last December, a mystery divorce-related filing by the director in Manhattan Supreme Court seeking “the enforcement or execution of a judgment or order.”

Insiders say that for an artist who set trends — both musically and aesthetically — for so many years, easing into her 60s gracefully is not easy. As someone who has spent most of her life dancing, Madonna’s now paying the price. During her tour, she referenced serious knee and hip injuries that caused her to cancel some dates and cry through others.

“It must be killing her to begin to feel ­irrelevant,” said Jeffries, who can talk on the record because he worked for Madonna before employees were forced to sign non-disclosure agreements.

“That girl was so smart, so driven, so ­focused, she could have been a major CEO. She had incredible powers of seduction and had more balls than any guy I ever met — more than any world leader,” he added.

“But she’s lived her whole adult life in a white-hot spotlight and now it’s dimmed to a 30-watt bulb. For someone like her, that’s gotta hurt. Her idea of hell is walking into a room and people either not knowing who she is or not caring.”

Madonna 2020 is “so not dope,” said a source who has worked with her in recent years.

She lashed out at “body-shamers” who mocked what appeared to be her Kardashian-esque butt implants on New Year’s Eve in 2018. She came across as tone-deaf when she claimed she felt “raped” by a 2019 New York Times profile of her even though it was written by a woman.

“Madame X,” her 14th studio album, was praised by critics but the gimmicky eye patch she donned as part of her character came off as too contrived. Her tour was well-reviewed at the start but devolved into a hot mess. There were reports of onstage tardiness and falls, clips of her crying onstage and a particularly alarming video of her ­hobbling up a flight of stairs with a cane.

But some in the know insist Madonna is still the expert at reinvention and say there’s a method to her apparent madness.

“What you’re seeing is a performance,” said one record-industry veteran who has known Madonna for more than two decades. “Nothing with her is unplanned. I feel for her about the [physical] injuries but she’s also [seemingly] playing the vulnerable-victim card because it’s worked so well for younger artists.”

And while some industry insiders say Madonna peaked a long time ago and is too old for a comeback, others disagree.

“She is crazy smart and will not fade away,” said Ed Steinberg, who produced her first video, “Everbody,” and has kept in touch er the years. “She’s reinvented herself 12 times and now she’s doing it again. Her most outstanding quality is needing attention. I would not write her off. She will rise again.”