Matthew Perry used to party with Bruce Willis and now prays for him every night

Matthew Perry is looking back on his wild partying days with Bruce Willis.

The Friends alum's memoir Friends, Lovers and the Big Terrible Thing takes fans behind the scenes of the iconic sitcom and offers candid insights into the actor's struggles with addiction. But in one chapter, titled "Bruce Willis," readers are given a glimpse of how the iconic action star used to let loose.

Perry, who got to know Willis during production of their comedy The Whole Nine Yards, reveals the pair would drink nonstop and that he struggled to keep his addictions at bay while the Die Hard actor knew when to quit.

"But there was a big difference between Bruce and me. Bruce was a partier; I was an addict. Bruce has an on-off button. He can party like crazy, then get a script like The Sixth Sense and stop the partying and nail the movie sober," Perry writes. "He doesn't have the gene—he's not an addict."

Perry also shared heartfelt moments with Willis that let him see the action star's "caring" side.

"Sometimes, at the end of the night, when the sun was just about to come up and everyone else had gone, and the party was over, Bruce and I would just sit and talk," Perry writes. "That's when I saw the real Bruce Willis—a good-hearted man, a caring man, selfless. A wonderful parent. And a wonderful actor. And most important, a good guy."

Yet Perry laments the two lost touch after that, adding he now prays for the ailing 67-year-old every night.

"And if he wanted me to be, I would be his friend for life. But as is the way with so many of these things, our paths rarely crossed after that."

He adds, "I, of course, pray for him every night now."

It was revealed in March that Willis was diagnosed with aphasia and would be stepping away from acting. At the time, Perry offered his support for the actor in a heartfelt post.

"Dear Bruce Willis, I'm so sorry to hear what you are going through, but you're still the coolest man I've met in my entire life," Perry tweeted. "You will remain in my prayers for a long long time."

"Maybe we should get together and watch the whole 10 yards and get a couple of hours of sleep," he added, joking about the 2004 sequel, which was critically panned and flopped at the box office.

Willis also appeared alongside Perry when he guest starred on season 6 of the hit NBC sitcom in 2000.

Friends, Lovers and the Big Terrible Thing is released on Nov. 1.

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