Princess Diana felt "extremely isolated" in the years before her death.
Princess Diana
The late royal had her life tragically cut short when she was involved in a fatal car crash in 1997, but a never before seen letter written by the Princess in 1991 has revealed she felt "continuously misunderstood" by those close to her.
The letter, obtained by the Daily Telegraph newspaper, was addressed to Princess Diana's close friend, the late interior designer Dudley Poplak and dated on December 3 1991.
It reads: "Dearest Dudley, I did so enjoy our lunch today - it was special for many reasons and in particular our conversation towards the end of our delicious meal.
"I do feel extremely isolated more than ever now, as I see what's coming to this country and this family.
"During the last couple of years I have been through a self-development programme which has brought a deep understanding of those who suffer and those who need love and support, wherever its in hospices or in the street.
"I feel that you believe in me, Dudley, and you've no idea what this means to me as I am continuously misunderstood by those around me.
"Please may we continue our conversation in January, when the pace of life isn't so fast and furious, as I'd care to ask for your advice and relay to you my inner thoughts.
"Lots of love from, Diana x."
The significance of the letter - which is now being sold by a private collector after Dudley's death in 2005 - comes as it was written just months before the "public falling out" which occurred when Andrew Morton published the controversial biography 'Diana: Her True Story' in 1992.
Chris Albury, from Dominic Winter Auctioneers, told the Daily Telegraph: "The letter sent in December 1991 is poignant in that it was written only months before all the public falling out following the Morton biography.
"She must have been feeling even more isolated from the Windsors at a time when her marriage had fallen apart and she had just told her version of her Royal life to Morton, knowing that she was about to let a genie out of the bottle which would change her life for better or worse.
"This heartfelt letter offers a unique window into Diana's inner-torment at that time."
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