Howard Stern and David Letterman Get Real About Beef Born From Rage, Ambition and Jealousy
21 Hollywood Co-Stars Who Hated Each Other

"I was angry with you, that you were on television, that you had an audience," Stern admits to Letterman in season finale of "My Next Guest Needs No Introduction."

Things could have gotten awkward between Howard Stern and David Letterman during the former's appearance on Letterman's "My Next Guest Needs No Introduction," but age and therapy have softened some of Stern's edginess. Whereas he might have lashed out inappropriately in his younger years, the 64-year-old shock jock now takes full responsibility for the tension that lingered between the two men for years.

One-time fast friends, Stern and Letterman found themselves embroiled in a bitter feud for many years. "I was just a young man full of rage and I was angry," Stern told Letterman. "I was angry with you, that you were on television, that you had an audience. There was no rhyme or reason to it. I could not love anyone, I couldn't respect anyone, I just thought this was who I was."

Stern attributes his evolution in part to simply growing up as he grew older, but even moreso he says that it was therapy that really helped him to look at the world in a new way. When Letterman asked him if a lot of that was a lack of self-esteem, Stern agreed, adding, "And I think just really a lack of self-examination. I think through psychotherapy I started to fall in love with life a little bit. I started to appreciate what was good."

A big part of that was his relationship with Letterman, which goes back decades now. Letterman and Stern used to be good friends, and would often get together with their wives and hang out. They shared intimate conversations about very real things over the telephone. Things took a turn, though, when Stern started talking about some of those conversations on his radio show. Understandably, Letterman wasn't happy about that at all.

"Words had no meaning to me. Words didn't hurt," Stern explained of how he justified some of the shocking things he would spout off about. "Of course, they hurt me if somebody says something bad, but as far as I was concerned, 'Oh everything's a joke. Words don't mean anything.'"

It was with that logic, that Stern made many enemies through his years on the radio, and blew up plenty of relationships, including his friendship with Letterman. "I had betrayed your trust and I was ashamed," he said.

Part of that was ambition, which the man both admitted shaped their earlier lives in negative ways. Both of them were so determined to succeed in their respective careers, they weren't present for their wives or families in the ways that they should have been. For Letterman, it was the birth of his son in 2003 that helped him reevaluate what was important. Stern found that through therapy.

"What about Beth? Was she an influence in some of this?" Letterman asked.

"I couldn't have been in a relationship with Beth until I'd opened up, because I wouldn't have been a good husband," Stern said, referring to his current wife. "I didn't want to screw it up again."

"My Next Guest Needs No Introduction with David Letterman" is a long-form discussion series featuring Letterman enjoying in-depth conversations with various people of interest from all walks of life, including Barack Obama, George Clooney, Malala Yousafzi, Jay-Z and Tina Fey. The season finale, featuring Howard Stern, is available for streaming on Netflix beginning Thursday, May 31.

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