My best friend of 20 years had sex with my husband at his bachelor party — this is how I found out

Bachelor party betrayal.

An Australian woman says she was left devastated after learning that her best friend of more than two decades had slept with her husband at his bachelor party.

The jilted wife, known only as Sophie, shared the saga in a letter sent to the hosts of the podcast “Everybody Has A Secret.”

“Last week my best friend Maddie admitted to me that she had sex with my husband at his bucks [bachelor] party,” Sophie wrote.

“As you can imagine, I’m devastated. My husband Tom and I have been married for 18 months and I had absolutely no idea that there were any issues in our relationship, let alone that he was capable of this level of deception.”

Sophie explained that she and Maddie had been friends for more than 20 years, and the women each knew how many men the other had slept with.

Maddie had always maintained that she slept with 18 different men.

But on a recent night out with several other gal pals, Maddie slipped up, saying she had had sex with 19 over the course of her lifetime.

“As soon as she said that, I corrected her,” Sophie stated. “She drunkenly said, ‘No, mine is 19’. She clearly realized in that moment she had made a mistake, because she tried to pathetically backtrack, but she was too inebriated to do it convincingly.

“In this moment I thought she’d probably just exposed herself for cheating on her partner Jack and was embarrassed,” Sophie continued.

A short time later, Sophie decided to speak privately with her best friend, asking Maddie whether she had been unfaithful to Jack.

However, Sophie got the shock of her life with Maddie tearfully confessed that the 19th man was her friend’s hubby, Tom.

Stunned, Sophie reportedly slapped her best friend across the face and fled the girls’ night.

Sophie says she still has no clue how Maddie ended up at her husband’s bachelor party.

A remorseful Maddie has repeatedly tried calling Sophie, but the betrayed bestie is refusing to answer the phone.

At the conclusion of the letter, Sophie revealed that her husband Tom is currently away on an overseas business trip and, while she plans to divorce him, she has not told him that she knows about his betrayal.

The jilted wife asked for advice on how to break the news to her husband. She also questioned whether she should tell Maddie’s partner, Jack, about Maddie’s manipulative move.

Video of the segment from the “Everybody Has a Secret” podcast has gone viral on TikTok, with viewers weighing in on what Sophie should do.

“Have a surprise welcome-home party and tell him in front of all his close friends and family,” one creative commentator wrote, saying she should maximize her revenge.

“I would tell Maddie’s partner IMMEDIATELY! He deserves to know the truth,” another declared.

“Get ‘I do. I did. I’m done’ printed on a cake in the shape of a broken heart — a photo of his face in one half and your best friend’s face in the other,” a third asserted.