That’s gotta hurt. Kailyn Lowry admits in a preview for the upcoming season of WE tv’s Marriage Boot Camp: Reality Stars that she once cheated on her now-ex-husband, Javi Marroquin, with his best friend. Javi took to Instagram on Wednesday, Sept. 6, to share the explosive clip.

In the sneak peek, the former couple get into a heated verbal disagreement that seemingly ends with Kailyn, 25, screaming, “I slept with your best friend!” Naturally, Javi seems shocked AF by the 16 and Pregnant alum’s admission. In his caption, the dad-of-one — who shares son Lincoln, 3, with Kailyn — opened up about how the revelation affected him.

“I’m not ready to relive these emotions all over again. Looking back at it, this might’ve been the hardest experience I’ve ever been through. Tune into @wetv this October,” he wrote, accompanied by a rather poignant (and TLC-inspired) hashtag: #don’tchasewaterfalls.

The clip comes just days after it was revealed on Monday night’s episode of Teen Mom 2 that the U.S. airman asked Kailyn for child support for little Lincoln. The Pride Over Pity author described Javi’s request as a “slap in the face.”

As previously reported, Kailyn and Javi — who were married for four years — announced their separation in May 2016. Their divorce was finalized that following December. While Javi went on to date other girls, Kailyn started a romance with Chris Lopez, the father of her third child, a son named Baby Lo. After their split, both parties accused each other of cheating during their relationship.

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Despite their attempt to salvage their relationship while taping MBC last fall, Javi previously said that the experience did not make things better. “Me, I went in there with open arms. I was open to the advice from the doctors and maybe we can make this marriage work. It’s easier for her to say no when you have something going on at home,” he told Us Weekly in February. “You’ll see.”

Marriage Boot Camp: Reality Stars returns to WE tv this October — and Teen Mom 2 airs on MTV Mondays at 9 p.m. EST.

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