A personal letter written by Princess Diana just days after her wedding to King Charles has come to light — and it reveals more than expected.

The beloved “People’s Princess” captured the world’s attention when she joined the royal family in 1981, marrying the now-King on July 29 at London’s St. Paul’s Cathedral.

Diana quickly stood out, not just as a royal, but as a compassionate figure — from warmly embracing an AIDS patient during a hospital visit to respectfully greeting Indigenous New Zealanders in their traditional style. She soon became much more than just another member of the monarchy — she became the princess adored by millions.

However, whispers of tension behind palace walls followed her for years, with many speculating she wasn’t always treated kindly. Now, this letter may offer a rare glimpse into that reality.

The note, dated May 30 and obtained by PEOPLE through Julien’s Auctions, was sent from Diana to Mark Simpson, a former footman at Buckingham Palace.

Before marrying Prince Charles, Diana briefly stayed in an apartment within Buckingham Palace. After their wedding, the couple moved into Kensington Palace.

In a letter dated just two days after their July 31 wedding, Diana reflected on her time at Buckingham Palace and expressed gratitude for the comfort she received during that lonely period.

She wrote to him:
“I just wanted to thank you for all your kindness + patience you’ve showed towards me since I moved into B.P. My stay was made so much easier by your company as it was so terribly lonely + we had so many laughs for that I can’t thank you enough.”

Rumors at the time suggested Diana felt isolated in the palace. In later interviews, she revealed she struggled with depression and received little emotional support from the Royal Family.

She continued in her note:
“Do hope you were able to enjoy Wednesday + that you liked my dress? I’m off to Britainia tomorrow, what with all those men around. I will have to keep a watchful eye on Evelyn!”