Lily Allen and David Harbour Separate After 4 Years — The ‘Marriage Has Been Crumbling’: Source (Exclusive)

Lily Allen and David Harbour are calling it quits.

The “Smile” singer, 39, and the Stranger Things actor, 49, have separated after four years of marriage, multiple sources confirm to PEOPLE.

“Her marriage has been crumbling,” an insider tells PEOPLE exclusively, “and they have split.”

Reps for Allen and Harbour did not immediately respond to PEOPLE’s request for comment.

Allen — who married Harbour in 2020 after meeting on the celebrity dating app Raya — alluded to a recent “tough time” on the Dec. 16 episode of her BBC podcast Miss Me? with co-host Miquita Oliver.

Though Allen did not offer additional details as to the source of her trouble, she said it was affecting her mental health and causing her problems with her eating.

The couple married in Las Vegas in 2020 in a ceremony that was officiated by an Elvis Presley impersonator. Allen’s daughters — Marnie Rose, 12, and Ethel Mary, 13, whom she shares with ex-husband Sam Cooper — also were in attendance.

Earlier this year, Allen offered a glimpse at some of the more unconventional aspects of her marriage to Harbour, such as her OnlyFans account, on which she sells pictures of her feet, and the fact that they controlled each other’s phone apps.

“I now have a kids’ phone called Pinwheel. It has no browsing capability and no social media, but you can still have Uber and Spotify,” she told The Sunday Times in May. “My husband is the caregiver on it, so he controls what I’m allowed to have as an app on my phone. I’m the controller of his as well.”

Then in July, she said on her podcast that Harbour thinks her OnlyFans account is “great.”

“At first, he was like, not turned on, but he was like, ‘Is this a kink for you?’ And I was like, ‘No, it’s totally not a kink,’ but maybe there’s something in the power element of it that’s slightly kinky for me,” she explained.

Allen also revealed on her podcast in June that she sometimes rejects her husband in bed.

“I wonder if I kink-shame my husband,” she said. “Because he often quite asks for things, and I’m like, ‘No, babe, it’s not happening.’ ”

“I’m not like, ‘You piece of s—, how dare you ask me to do that!’” Allen joked. “I’m just like, ‘Hmm, headache. Little headache, got a bit of a headache — maybe not tonight.’ ”

In September 2023, Allen marked their three-year wedding anniversary with a sweet post on Instagram that she captioned, “3 years with this guy, 2nd best decision I ever made. 1st was that dress.”

In November 2023, Harbour opened up to PEOPLE about finding his perfect match in Allen.

“Let me tell you, my wife likes when I go to work because it’s nice for her to have her life and me to have my life and for us not to just annoy each other by being around all the time,” he said at the time. “We have these two kids, and it’s so great. We get to raise them and stuff, and as our marriage continues, we grow closer and closer.”

Allen and Harbour were first linked in January 2019, when they attended the BAFTA Tea Party together, and later confirmed heir romance that October.

Harbour announced news of their wedding with a photo on Instagram, which he captioned, “In a wedding officiated by the king himself, the people’s princess wed her devoted, low born, but kind credit card holder in a beautiful ceremony lit by the ashen skies courtesy of a burning state miles away in the midst of a global pandemic.”

Over the years, the two spoke openly about their relationship. In an interview with The Sunday Times in October 2020, Allen shared how she was hoping to have kids with Harbour.

“I think so. Especially now Marnie’s getting so big,” she said.

In June 2021, Harbour opened up on Jimmy Kimmel Live!, revealing that a conversation he had with Allen’s daughters while riding their bikes led him to get married to the singer.

“The little one was riding along and she was going like, ‘David, dad, David, dad.’ Because the D got her confused,” the actor recalled. “And the older one got very upset with that, which I understand. She was like, ‘He’s not our dad! He’s not our dad!'”

Harbour continued: “And then the younger one was like, ‘Well what is he? He’s kind of our dad.’ She’s like, ‘No he’s not, he’s our stepdad.’ And she goes, ‘What is he?’ And she goes, ‘He’s just some guy in our lives!'”

The actor confessed that the girls’ conversation motivated him to take the next step with their mother. “I was like, ‘I need to marry this woman,’ ” Harbour joked. “Because the emotional fallout … “

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During an interview with British GQ in July 2022, the Stranger Things star recalled the early days of their romance, noting how he knew something was different with Allen after their third date.

“I was in this phase where I was like, ‘I’m just going to be brutally honest about everything,’ because why lie? And I told her something about my life, about my beliefs,” he said. “It would take a really extraordinary person to be accepting of the things that I said.”

He added, “And I remember thinking: Wow, that’s somebody I want to be around.“

Prior to their split, the couple was often seen with the girls out and about. They attended the Stranger Things season 4 premiere, a screening of Marvel’s Guardians of the Galaxy Vol. 3, and most recently Taylor Swift’s Eras Tour.