John Stamos shared a story about finding his then-girlfriend Teri Copley in bed with Tony Danza in his new memoir, "If You Would Have Told Me."

Stamos and Copley dated back in the 1980s before his marriage to model Rebecca Romijn. At the time, Stamos was "dumbstruck and goofy in love" with Copley and described finding her in bed with Danza as his "worst nightmare." However, the "Brain Donors" actress insisted the two weren't actually together anymore when the incident happened.

"John has a very different recollection of what transpired decades ago," a representative for Copley told Fox News Digital.

"I wondered, 'What was John doing there?' because we had broken up," the actress also told People magazine. "He just looked at me and shook his head, and walked away."

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Stamos recalled things going well between him and Copley for over a year before he noticed she had begun to distance herself from the "Full House" actor.

"I call her from the road, but the girl who breathlessly picked up the phone after one ring is now giving me busy signals and dial tones," Stamos wrote in his memoir, via Entertainment Weekly. "When I get home, I call her throughout the day and into the evening. No response. Strange. We've gone from talking on the phone every few hours to silence."

Stamos drove over to Copley's home but discovered an unfamiliar car in the driveway. The home was dark and locked, but Stamos chose to check out the guest house.

"The blinds are closed, but the door is slightly open," he said in the book. "I take a peek inside and see four feet protruding from the shabby-chic, floral-print duvet that once kept me warm. My Tiny Dancer is in bed with Mr. Porsche Speedster. They are sleeping. I can't tell who he is, but I recognize Teri's a-- barely covered by the sheets."

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At the time, Stamos didn't know it was Danza. "But I remember running down the driveway with tears streaming down my face and I didn't want anyone to see me," the actor told People magazine.

Stamos stopped and took a signed poster of Copley out of the unfamiliar car parked in the driveway.

"I stare at the two-dimensional, half-dressed woman that I thought I knew. She's signed the poster, with little hearts, 'My Dear Tony, I'll love you forever. XO, Teri,'" he recalls. "Tony? Who the hell is Tony?"

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The actor admitted he didn't put together who the unknown man in bed with Copley was until he was listening to Elton John on the way home, discovering "the name of [his] rival."

"Hold me closer, Tony Danza," he wrote.

Representatives for neither Stamos nor Danza immediately responded to Fox News Digital's request for comment.