In many respects, David Letterman is like a father to Howard Stern. Of course, David Letterman is 73 and Howard is 66, so it wouldn't be possible. But in a symbolic sense, it is. And like many father/son relationships, Howard's dynamic with David Letterman wasn't always positive. This reflects Howard's own complicated past with his father.

Howard has feuded with many celebrities over the years and David Letterman is no exception. Except for the fact that the two have always remained quite friendly with one another on air. Howard has been a guest on David Letterman's now-iconic late-night talk show almost more times than any other celebrity. David has returned the favor by appearing on SiriusXM's The Howard Stern Show a handful of times, even as recently as April 2020.

Respect runs deep between them. And, even though both are exceptionally reclusive, Howard and Dave have both stated that they consider one another "a friend".

But to Howard, David was much more than that... and that caused some problems...

David Letterman Changed Howard's Career

While Howard Stern was a judge on America's Got Talent, he was interviewed about David Letterman's 2015 departure from his iconic CBS late-night talk show. Extra's AJ Holloway snagged a moment with the radio legend on the red carpet.

"Let's talk about Dave Letterman, a friend of yours, announcing his retirement. What are your thoughts on it?" AJ asked him.

"Oh, I'm filled with a lot of thoughts. I'm actually really affected by it," Howard confessed.

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"To watch him retire... it seemed unthinkable really. Because he's always been there. And personally, he's been there for me in a big way. When I was a young guy, I was new to NBC radio... NBC did not like me. Management was kicking the hell out of me. And I get a call from Letterman, 'Hey, I wanna see you on my national show'. So, this is the first time a local DJ is going to be on national TV as a guest. And Dave really enjoyed me and had me back. I did a tremendous amount of appearances. Especially early on in my career. I used to go on all the time."

In fact, Howard had been one of David Letterman's favorite guests that he even had him on (alongside iconic comedian Don Rickles) one of his last shows. According to Rolling Stone, Howard always gave David's show a much-needed edge. While some of Howard's comedy often made David uncomfortable, he knew it was ratings gold...

But Howard's edge and brutal honesty went a little too far...

Howard And David Had A Falling Out

Luckily, Howard and David rekindled their friendship before David retired from his CBS show. The friendship between them makes sense given the fact they are both highly idiosyncratic, reclusive, and both have always refused to bow to their corporate bosses. Then there's the fact that both have feuded hard with former Tonight Show host Jay Leno.

But segments on Howard Stern's Show rubbed the late-night titan the wrong way. During a 2013 interview on The Late Show, Howard publically admitted to apologizing to David Letterman for abusing their friendship.

"You and I were on our way to being best buddies," Howard told David before letting the audience know that they became so close that David would call him at his house.

"I was out of my mind. I really truly was," Howard continued. "I think I did a lot of things on radio that I didn't need to do."

"Just to get attention," David added.

"To get attention. And you know, literally, we would have nice conversations and instead of valuing that --- because here you are, someone who was in the industry who was nice enough to call me. And I felt we shared a lot of things in common, it would have been nice to have that bond. But I was at a time in my life that nothing mattered except the success of my radio show. And I was literally insane. And I would go on the air, and rather than value our friendship I would go and destroy it. And that's a disturbing human being."

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Howard's time in psychotherapy, as well as a daily practice of meditation, brought him to the understanding that he was doing David wrong by exposing private details of their conversations for ratings. Not only that, but Howard had really offended David's wife, Regina in one of his rants.

During Howard's final appearance on The Late Show With David Letterman, he brought Regina a painting he had created for her. This was huge for Howard as he has been very secretive about his painting and has only given a few away. Attached to the painting was a letter of apology that he wouldn't share with the audience.

Psychotherapy Changed Howard's Relationship With The Lettermans

Howard has spoken a lot about how psychotherapy changed his life and ultimately made his relationships stronger. This includes the one he shares with David Letterman and his wife, Regina.

After David retired from his CBS late-night show, Howard was asked to appear on David's new Netflix show, My Next Guest Needs No Introduction.

Howard was one of the first people asked to be featured. It was a huge honor. However, Howard is just as reclusive as David and therefore REALLY didn't want to do it. But he helped promote David's show by telling his audience what a pain it was to prepare for it. Nevertheless, it happened and Howard just rocked it. Especially when explaining how he fixed his relationship with David.

“I think through psychotherapy I started to fall in love with life a little bit. I started to appreciate what was good. And one of those things was my relationship with you — that I could appreciate what you had done for me. I had betrayed your trust and I was ashamed. Here, the reality was I loved you and I really felt strongly about you.”

Howard and David have remained close ever since. David has been featured on The Howard Stern Show and was even the sole guest interviewed at Howard's 60th Birthday show. While they don't spend a lot of time hanging out, the two have nothing but positive things to say about each other and speak as frequently as they can.

Next: How Craig Ferguson Really Feels About Not Getting The Letterman Gig