The Mystery Woman at the Center of Lily Allen and David Harbour’s Split Has Finally Been Revealed — and Fans Can’t Believe Who It Is.NN

The woman who allegedly had an affair with Lily Allen’s estranged husband, David Harbour, has been revealed to be Natalie Tippett.

In an interview with the Daily Mail, the costume designer, who met the “Stranger Things” actor while filming a movie in New Orleans in 2021, reacted to Allen singing about the affair on her newly released album, “West End Girl.”

On the song “Madeline,” Allen, 40, sang about Harbour breaking the rules in their “open” marriage.

“Of course I’ve heard the song,” Tippett told the outlet while allegedly rolling her eyes.

“But I have a family and things to protect. I have a 2-and-a-half-year-old daughter, and I understand this is going on,” the single mom added.

“It’s a little bit scary for me.”

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Tippett, 34, worked in the costume department while Harbour, 50, starred in the 2021 Netflix film “We Have A Ghost.”

Their alleged affair reportedly started shortly after filming began.

After filming concluded, the “Hellboy” actor allegedly flew Tippett out to his home in Atlanta — without Allen’s knowledge.

However, the “Smile” songstress found out about her husband allegedly cheating when she found texts on his phone.

When Tippett was asked by the Daily Mail if she knew her private texts with Harbour were being used in Allen’s songs, she replied, “Yeah. I just don’t feel comfortable talking about it at the moment.”

Page Six has reached out to both Tippett and Harbour for comment but did not immediately hear back.

In February, news broke that Allen, who married Harbour in 2020, and the actor were divorcing. The “Hard Out Here” singer then revealed that she had gone to a treatment center for “emotional turmoil.”

Allen filed for divorce last month.

Harbour has remained mum on the breakup and the infidelity rumors. In April, the “Black Widow” star awkwardly dodged questions about his estranged wife.