"John Stamos detailed the emotional moment he caught Tony Danza in bed with his girlfriend Teri Copley back in 1985 in his new memoir If You Would Have Told Me, which hits shelves this Tuesday. The 60-year-old eighties heartthrob had initially believed he would 'spend the rest of my life with' the 62-year-old actress, whom he reportedly dated from 1984-1985. 'She's everything I'm looking for in a woman,' John wrote in his 352-page tell-all in an excerpt obtained by EW.'She has an adorable daughter, Ashley, from a former relationship, and I love the idea of stepfatherhood. I'm starting to imagine our little family coming together. I'm dumbstruck and goofy in love.' While out of town 'doing car shows and gigs,' Stamos starts to sense Teri distancing herself from him before totally ignoring his calls. The two-time Primetime Emmy nominee decided to confront Copley at the guesthouse they would occasionally stay at, which was located on her ex-husband Chip Mayer's San Fernando Valley property. 'A black 1957 Porsche 356 Speedster, vintage convertible. Strange. I shuffle to the car with my stomach sinking and take a quick look inside,' John wrote. 'There's a hairbrush, keys, boxing gloves, and a half-unrolled poster of my girlfriend, naked, barely covered by a white sheet. Half of her butt is showing. I've never seen this poster before.' Stamos noticed the guesthouse door was 'slightly open' and saw the blonde bombshell's 'a** barely covered by the sheets' while sleeping in bed with 'Mr. Porsche Speedster' who had 'ripped abs and muscular body.' [It's] my worst nightmare,' the Orange County native wrote. 'I try to hold back tears. Time slows until I'm frozen. I can't breathe. A few tears roll down my face, and it pi**es me off. They snap me out of my daze, and I feel angry and confused. I could explode.' John pondered the idea of pulling 'him out of the bed by his hair, kicking him in the nuts, and beating his a**' but instead decided to 'run like hell.' On his way out, Stamos stole the poster from the Porsche and saw it was inscripted with hearts: 'My Dear Tony, I'll love you forever. XO, Teri.'It wasn't until the honorary Beach Boy was listening to Elton John on the drive home that he realized 'the name of my rival: Hold me closer, Tony Danza.' But John doesn't hold animosity against the 72-year-old Emmy nominee, in fact he thanked him later on in the book for paving the way for portraying a handsome unlikely caretaker on an ABC sitcom. 'If you would have told me the day I walked into that room and caught my true love in bed with another guy that his show Who's the Boss? would launch Full House into a bona fide hit, making me a household name,' Stamos wrote. 'Well, what can I say? Thanks, Tony Danza.'