Transcript for Howard Stern on the moment he realized he needed to make life changes: Part 2
We're such an odd couple. Show the book and -- this is difficult for me. Reporter: When you interview Howard Stern, the mic is always hot. This might be a shock to people. George and I are actually we get together for dinner with our wives quite often at my house. And by the way, full disclosure. George is one of the best dinner guests. But you cause a little bit of a rift. And I'll tell you why. We're sitting at dinner, and alley, George's wife will say, George is an intellectual. Weren't you some sort of Rhoads scholar or something? Weren't you a priest or something? This is coming to the Howard Stern show. Let me take five minutes for this. But inevitably, Ali will go, George and I have sex every night. I'm like, and George doesn't laugh. He sits there like this. You never let on. I don't know what's going on. And then after you leave, you and Ali leave, I go, did you hear that? My wife, I love her. She's a wonderful woman, a beautiful woman. We have sex, you know, you know, normal couples, George. You know, I didn't know, and you, I never think of you as a sex fiend. And I said, can you picture George and Ali every night? Reporter: Completely hijacked right here. That can't be true. Reporter: It is not true. We do well though, we're doing fine. I feel bad. I go something's wrong with my marriage. Reporter: Today stern is happily married to his second wife. With the help of this therapy he's doing the best work of his career. I believe blew him right out of the water, why? I'm thinking I'm the most important thing here. Robin Williams goes on about something. My audience will tune out. I have to keep their interest. It was such a pressure that I couldn't be gracious enough to allow robin Williams. Imagine the arrogance of me, thinking robin Williams can't hold my audience. Reporter: You write about that. You tried to reach him and apologize. Yeah. When I finally realized that a, it's okay to be a fan of someone, you know, I've been such a hard-ass on the air. I had such a desire to have all the audience for me. That I couldn't be gracious. There's no room for anybody else. So I couldn't be a fan of anyone else. And here I am a huge fan of robin Williams. I've seen everything he does. His stand-up is mind-blowing, and he comes into my studio, and what do I do? I go hey, I read you're having sex with your nanny, you left your wife for your nanny or something like that. Now that's clobbering somebody over the head. That doesn't lead to discussion. It was insulting to him. But all I as being the man. Reporter: So when you walked off the air that day, you said, I nailed it? Got it? Yeah, yeah. I was clueless. Reporter: In his book, stern writes that it took him 20 years to work up the nerve to apologize, but Williams died before he got the chance. And facing his own mortality is one of the reasons stern wrote this book. I had been diagnosed with kidney cancer. And I had to go in for surgery, and I was freakin' out. I go, this can't be. And they had told me, it was 95% chance it was cancer, and it turned out not to be cancer, it was like a miracle for me. Reporter: When it passes, do you have that Winston Churchill feeling of being shot at and missed? Yeah, I think that's why I wrote this book. It brought me to the reality, you're not going to live forever. These interviews represent to me the best of me. Howard Stern's new book is available in stores now.
This transcript has been automatically generated and may not be 100% accurate.