Samantha Cohen, the Queen's former assistant private secretary, tells PEOPLE that "Windsor was her home and she loved being there."
"She died in her favorite place and was laid to rest in her favorite place alongside her husband and other members of her family," Cohen shares.
Cohen, who was in attendance at the committal service, says it was "very odd" to be at the chapel without Queen Elizabeth.
"It felt really strange to be in Windsor without her as you'd see her everywhere," she tells PEOPLE. "It was her home, where she would drive around, or be riding her horse. It feels odd to be there without her."
Cohen adds that it was a "very moving service" in honor of the late Monarch.
"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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Cohen reveals that as the late monarch's coffin was being lowered, "you could hear a pin drop at that moment" in the chapel, adding "It's hard to fathom that she's gone. It doesn't seem real."
She says while it was "lovely" to see the Queen's extended family, they "looked tired. It was a shock and now it's real. And the real mourning starts. The reality of life without the queen starts now."
Prince Harry and Meghan Markle sat next to Prince William, Kate Middleton and their two older children, Prince George and Princess Charlotte, sat in the front row of the pews at the committal ceremony.
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Directly behind them was King Charles III — with the seat directly in front of him deliberately left empty — beside him was his wife Queen Camilla, along with sister Princess Anne, brother Prince Andrew and their respective families.