Prince Harry was "worried" about returning to the U.K. to attend the funeral of his grandfather Prince Philip because he feared the trip would bring back the trauma of losing his mother.
The Duke of Sussex was just 12 when his mum, Princess Diana, was killed in a car crash in Paris, France back in 1997, and ever since the tragedy, Harry has suffered from post-traumatic stress disorder.
He flew back from his new home in California in April to join his family in mourning Prince Philip's passing, but the whole time, the 36-year-old was wracked with nerves.
"I was worried about it, I was afraid about it," he told The Associated Press of his trip to the U.K., which he made solo as his wife Meghan, Duchess of Sussex was advised by doctors not to fly as she is pregnant with the couple's second child.
To cope with the mental health struggles, Harry leaned on techniques he had learned in therapy to pull him through the private memorial service, which was held at St. George's Chapel, in the grounds of Windsor Castle - the same venue in which he had exchanged vows with his wife back in 2018.
"Going through the motions and being able to lean on the toolbox, and lean on the learnings that I've grown from over the past, it definitely made it a lot easier, but the heart still pounds," he said.
Harry admitted simply being in London was enough to make him anxious because it's been a "trigger" for him since the death of Diana.
He confessed, "For most of my life I always felt worried, concerned, a little bit tense and uptight whenever I fly back into the U.K., whenever I fly back into London."
Harry details the trauma he suffered behind closed doors in the years following his mother's passing and how he's been processing the pain through therapy in his new Apple TV+ mental health series, The Me You Can't See, which he co-produced with Oprah Winfrey.
He also opens up about the struggles which led to his high-profile split from the royal family, which prompted the royal couple and their two-year-old son Archie to relocate to the U.S. last year.