According to my friend, the husband sent the messages on Grindr approximately a month ago, along with sending illicit nude pictures and asking for sex.
My friend doesn't think the husband recognised who he was talking to, otherwise "he would block me out of fear I'd tell his wife", but now the husband's profile has appeared on another gay application, Scruff, the guilt is beginning to eat away at him.
"He probably wouldn't know I existed unless someone prodded him," my friend said.
One group of friends thinks my friend should be upfront with the wife, or confront the husband and force him to fess up. But either way, he would be interfering.
"Should I just pretend I never saw it?" he asked.
It comes as The Atlantic ran an interesting story which reported between 1.2 million and 2.4 million couples in the United States are trying "ethical non-monogamy".
"Ethical non-monogamy, what the hell is that?" I hear you ask.
The term popped up about 2014 and has been paving the way for the sexual revolution of couples ever since.
"Ethical non-monogamy is a great term that encompasses all the ways that you can consciously, with agreement and consent from all involved, explore love and sex with multiple people," Author Gracie X wrote in the Huffington Post.
Ms X said she "opened her marriage" 10 years ago because "though we still adored each other, after 20 years of marriage our sex life was fairly dormant".
"As time passed ... our open relationship evolved into something entirely different and unexpected — me with my new boyfriend, my husband and his new girlfriend, and all our kids living under pretty much one roof."
Ms X described the "many flavours" that encompassed ethical non-monogamy in couples, including polyamory — the art of inviting more than just two into a relationship — and swinging, where couples openly engage in no strings attached sex with other people.
Last year, Rolling Stone claimed that "millennials are increasingly embracing" the movement and polyamory in the United States "is treated less like a novelty and more of a valid relationship model".
"People say, you're just playing the field, you want too much, you have to settle, you have to compromise, but that never felt right to me, I never understood why I'd have to give up some important need or desire of mine just because someone expected me to," one man told Maria Rosa Badia for her short film Polyedric Love, which premiered on the The Atlantic last month.
The film is described as featuring "honest conversations with couples about the rewards and challenges of their unconventional relationships".
"You can have your cake and eat it too as long as your communication is above board," one man said.
"To me, I wish I'd learned it when I was younger. That level of honesty translates into so many different parts of my life now. I'm not afraid to tell the truth now or be honest, I don't have to keep anything for fear of hurting someone."
So, does this help my friend? Probably not. Telling his friend that her husband is cheating on her on a gay application and maybe they should consider the idea of an open relationship would probably sink their friendship faster than the Titanic — but filmmaker Badia does make an interesting point.
"I was moved by the couples' honest rapport with their partners about their individual needs," Badia told The Atlantic, "and how they had a very straightforward communication about it.
"I realised that what's necessary for a non-monogamous relationship to work — mutual respect and communication — is absolutely necessary for a monogamous relationship, too."
