The red haired Royal, 32, had so much pent-up aggression inside him that he was on the cusp of becoming incredibly violent.
He opened up about his psychological trauma, which included going off the rails for most of his twenties and two years of “total chaos”.
But some time in the boxing ring managed to put things into perspective, and he is now “able to take my work seriously, able to take my private life seriously as well, and able to put blood, sweat and tears into the things that really make a difference and things that I think will make a difference to everybody else”.
Prince Harry, who said his brother, Prince William, was the one who intervened and told him to get help because his behaviour “wasn’t normal”, revealed that he never dealt with the emotions surrounding his mother’s death in a Paris car crash.
He said he used to walk around saying “life is great” when, in reality, that was far from the truth.
Prince Harry said he took up boxing to get rid of aggression during mental health blip
Prince Harry said: “I have probably been very close to a complete breakdown on numerous occasions when all sorts of grief and all sorts of lies and misconceptions and everything are coming to you from every angle.
“My way of dealing with it was sticking my head in the sand, refusing to ever think about my mum, because why would that help?
“I thought it's only going to make you sad, it's not going to bring her back. So from an emotional side, I was like 'right, don't ever let your emotions be part of anything.’”
Prince Harry in pictures Tue, March 21, 2017
Prince Harry royal visits around the world and a mixture of all the charitable work he's done.
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Prince Harry during a visit to Hamilton College on March 21, 2017 in Leicester
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Prince Harry said he was on the verge of punching someone
He said: “Everyone was saying boxing is good for you and it's a really good way of letting out aggression.
"And that really saved me because I was on the verge of punching someone.”