Jimmy Kimmel and Matt Damon have been feuding for years, and on Monday’s Jimmy Kimmel Live!, the frenemies took their feud to couples therapy.

Damon first came out onstage dressed as Kimmel’s other guest for the evening, Dr. Phil McGraw, sporting a bald cap and talking in an exaggerated Southern accent, he told Kimmel the costume was part of his effort to "finally" be a guest on the comedian’s late night.

"You said that I could be on the show today, when we were in therapy," Damon protested.

"I said I would try and get you on the show tonight," Kimmel cautioned. "We have a very, very busy night."

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The two couldn’t agree on who said what, so they took it to the tape, cutting to a pre-taped bit of their "couples therapy" session.

"He promised me, over a decade ago. that I was gonna be able to be a guest on the show," Damon told the pair’s therapist. "I come and I wait, every night."

"I try to get him on the show," Kimmel protested. "We have a one-hour show every night. We have other guests -- which he doesn’t care about, obviously -- I have a monologue to do, we have a band, sometimes we have important commercials to run…"

"This is what he does so well," Damon retorted. "He talks the talk and he makes me think I’m crazy."

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In their "therapy" session, the two poked fun at Damon’s movie We Bought a Zoo as well as the 44-year-old’s looks.

"I imagine it would suck to be him," Kimmel responded when asked to put himself in The Martian star’s shoes. "First of all, look at him...I mean just look at his face and look at his body. It’s not a movie star face and it’s not a movie star body."

"He is verbally abusive to me and couches it as truth," Damon responded.

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So, could the two say anything nice about the other?

"I like some of his friends," Kimmel revealed. "You know, Ben."

"To be fair, I like his show," Damon admitted. "I wouldn’t have waited for 12 years to get on if I didn’t like the show."

Ultimately, the actor said he’d commit to waiting 12 more years, and Kimmel promised to "try harder" to get his friend on the show.

"Just not tonight," he deadpanned. "Because this counselling thing has gone on for a pretty long time."

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