Connolly says he was "gutted" after Cox was photographed on a date with Bobcat Goldthwait, while all three were on the same WB show together.
Kevin Connolly is looking back on one of the most difficult breakups of his life.
While appearing on Christine Taylor and David Lascher's Hey Dude... The 90s Called! podcast Monday to discuss his career as a '90s child actor, Connolly opened up about the heartbreaking moment he found out then-girlfriend and Unhappily Ever After co-star, Nikki Cox, was cheating on him.
"Nikki Cox, who played my sister, and I started dating between seasons four and five," Connolly said about working on the '90s sitcom.
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View Story"A couple of days before the table read for season five… Jeremy London called me and said, 'Kevin, get in your car…' He said, 'Get in your car, drive down to 711 and open the National Enquirer,'' the Entourage alum recalled.
He continued, "I get in the car and drive up the street. I've got a knot in my stomach and start flipping through into the Enquirer."
It's then Connolly finds out that Cox had been having an affair with their co-star, Bobcat Goldthwait.
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View Story"And there's a picture of Bobcat and Nikki dating. And then the next day, or like two days later, I had to go into that table reading, and we had to just gut out 24 weeks of misery," Connolly shared.
The affair not only left Connolly heartbroken, but deeply affected the longtime actor, who said he struggled filming the final years of the series, which ran from 1995 to 1999, alongside Cox and Goldthwait.
He said that the breakup was the "first time" he thought he was "going to die."
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View Story"It was pretty terrible. Yeah, I was gutted. I couldn't sleep. It was one of those jobs," Connolly added.
Weighing in on the public nature of it all, Taylor said, "There's nothing worse than for you to find something like that out publicly is horrendous."
With Lascher adding, "And the guy you're working with."
Cox and Goldthwait would continue to date through the '90s, even getting engaged before calling things off in 2005.
While it was a devastating time for Connolly, he revealed that he and Cox have stayed in touch over the years, and still "catch up once in a while."