John Stamos Says He Caught His Girlfriend In Bed With Tony Danza

John Stamos says he was beyond broken after he found Teri Copley, whom he dated in the ’80s, cheating on him with fellow actor Tony Danza.

In his forthcoming memoir, “If You Would Have Told Me,” Stamos said he walked in on the duo together. He described the alleged incident as “physically painful” in an interview with People magazine published on Monday.

“I can’t explain it, but I would’ve rather been punched in the nose again or something because the pain is so overwhelming,” the “Full House” star said.

“Looking back, it’s like, probably, she wasn’t the right girl for me,” Stamos admitted. “So seeing him, realizing it was him and stuff, it was hard. I mean, it was awful.”

The “Grandfathered” actor, now 60, said he stopped by Copley’s guest house, where he found the model-actor in bed with a man with “ripped abs.”

“At first I was like, ‘I’m going to kick his…’ I didn’t know it was [Danza] yet,” Stamos claimed. “I see his abs. I’m like, ‘Maybe not. Fuck it.’”

“And I ran. But I remember running down the driveway with tears streaming down my face and I didn’t want anyone to see me.”

While Stamos said he didn’t know the man was Danza at the time, he writes that he was able to put the pieces together after finding a saucy poster of Copley signed “My Dear Tony: I’ll love you forever. XO, Teri,” in the backseat of Danza’s Porsche, which was parked in the driveway.

Copley remembered their relationship timeline a bit differently, though.

“I wondered, ‘What was John doing there?’ because we had broken up,” she told People of Stamos’ abrupt appearance. “He just looked at me and shook his head, and walked away.”

Danza’s team did not immediately return HuffPost’s request for comment.

While Stamos said he was completely devastated, he partially credited his romantic rival for the success of “Full House,” which followed Danza’s hit series “Who’s The Boss?” during its original timeslot on ABC.

“Back then, you go, ‘Life isn’t fair.’ And then, ‘Oh, wait a minute. It got evened out,’” Stamos remarked. “I honestly believe if we didn’t follow his show in the summer, that would’ve been one and done for that show ‘Full House.’”

Stamos’ book “If You Would Have Told Me: A Memoir” comes out Tuesday via publisher Henry Holt and Co.