Paul McCartney sat down for an interview with “CBS Sunday Morning” to promote the release of this new album, “McCartney III”, on which he played all the instruments (as he did on the predecessors, 1970’s “McCartney” and 1980’s “McCartney II)”.

During the conversation, McCartney was asked whether he was still processing the murder of John Lennon, which took place 40 years ago this month.

“I’m not sure I am,” said McCartney. “It’s very difficult for me, and I occasionally will have thoughts and sort of say, ‘I don’t know, why don’t I just break down crying every day?’ Because it’s that bad.”

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Does he sometimes break down and cry? “Not every day, you know? There will be times that I just have memories and just think, ‘Oh my God, it was just so senseless,'” he admitted.

Asked if he thought Lennon would still be producing music, as McCartney is, the former Beatle responded, “Yeah. He was showing no signs of slowing up. You know, he was still making great music. The question is, would we have ever got back together again?”

Asked for insight on the answer to that question, McCartney admitted, “I don’t know! We don’t know. We were friends. That was one of the great things about it. You know, I don’t know how I would’ve dealt with it. ‘Cause I don’t think I’ve dealt with it very well. You know, in a way, you know … I wouldn’t be surprised if a psychiatrist would sort of find out that I was slightly in denial. Because it’s too much.”

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In fact, McCartney revealed that he still has dreams about Lennon, and often thinks of him when he writes songs.

“What happens if you’re in the car and a Beatles song comes on?” asked interviewer Seth Doane. “What do you do? You turn it up? Turn it off?”

“Turn it up! Turn it up! Sing along with it,” said Sir Paul. “It always takes me back to the session, you know, it always reminds me, ‘Oh yeah, I remember John was there, Ringo was there, where we did this one. Yeah, yeah …’ It’s great, it takes you right back like a flashback.”