Royal Family's 'Real Mourning Starts' After Queen's Funeral: 'It Was a Shock, and Now It's Real'

MARCO BERTORELLO/AFP via Getty Prince William and Prince Harry

Queen Elizabeth's former assistant private secretary says the "real mourning" can now begin for the royal family following the late monarch's funeral and committal service on Monday.

Samantha Cohen tells PEOPLE that the royal family will need to adjust to a new normal after the death of the Queen, who died at age 96 on September 8 at Balmoral Castle in Scotland.

"It was a shock, and now it's real. And the real mourning starts," Cohen tells PEOPLE in this week's cover story. "The reality of life without the Queen starts now."

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Cohen, who was in attendance at the committal service, reveals that as the late monarch's coffin was being lowered, "you could hear a pin drop" in the chapel, adding, "It's hard to fathom that she's gone. It doesn't seem real."

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Cohen adds that it was a "very moving service" in honor of the late monarch.

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"It was very intimate as all the Queen's personal staff and her households were there," she says. "It signaled the transition to the King as we ended with 'God Save the King.' "

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"There was a lot of camaraderie — it was like a big reunion for all those who'd worked for her for years but had left. She was bringing together those who'd worked for her for years like her private secretaries and other staff and she was bringing them all together these last days," she continues. "She included everyone who'd worked with her. It was very inclusive and wasn't hierarchical with her personal staff sitting right on the front."

Cohen also says the service reflected the Queen's ability to bring people together.

"It was about personal relationships — that's what was so beautiful about the Queen," she says of the service. "She accepted people from all walks of life and the service reflected that. The uniting force was everybody's love for the Queen. She made it special because she made sure that everybody felt important and included."

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After her state funeral and committal service, the Queen was buried at King George VI Memorial Chapel on Monday evening.

The late monarch was laid to rest beside her husband of 73 years, Prince Philip, during a private burial service, Buckingham Palace confirmed.

Prince Philip, who died at age 99 in April 2021, was moved from the Royal Vault beneath the chapel, where he was temporarily interred, to be by her side.

The palace also paid tribute to the Queen on social media alongside a beautiful photo of her enjoying the Scottish Highlands, writing, "'May flights of Angels sing thee to thy rest.' In loving memory of Her Majesty The Queen. 1926 - 2022."