EXCLUSIVE: Heartbreaking Reasons Princess Diana Went to Her Grave Ashamed About Her 'Horrific' Appearance at Prince William's Christening

Princess Diana went to her grave ashamed of how she looked and felt during the christening of her first son, Prince William – confessing the day "couldn't have been worse" and left her feeling like an afterthought in the ceremony, RadarOnline.com can reveal.

The event took place at Buckingham Palace on August 4, 1982, just six weeks after William's birth on June 21.

Though it marked an important milestone for the heir to the throne, Diana – then only 21 and barely a year into her marriage to Prince Charles– was already struggling with postpartum depression and isolation.

"She felt pushed aside and deeply embarrassed," one insider said. "Diana said nothing about the day had been done with her in mind – not the schedule, not the pictures. She thought the photos were awful and showed her looking fragile. That sense of shame never left her."

Speaking to biographer Andrew Morton for his 1992 book Diana: Her True Story, the Princess of Wales recalled how little input she had in the planning.

"Nobody asked me when it was suitable for William," she said. "11am couldn't have been worse. Endless pictures of the Queen, Queen Mother, Charles, and William. I was excluded totally that day.

"I felt desperate because I had literally just given birth. William was only six weeks old, and it was all decided around me. Hence the ghastly pictures."

The christening, conducted by the Archbishop of Canterbury, Robert Runcie, took place in the palace's Music Room – a location traditionally used since Queen Victoria's time.

William wore the royal family's antique christening robe, while the date also coincided with the Queen Mother's 82nd birthday, ensuring the focus was not solely on Diana.

"I wasn't very well, and I just blubbed my eyes out," Diana told Morton. "William started crying, too. Well, he just sensed that I wasn't exactly hunky dory."

The shame she felt at the event reflected a deeper unhappiness in her marriage.

Diana had married Charles in July 1981 in what was hailed as a fairytale wedding, but within a year she said the cracks were already showing.

She described feeling unsupported and sidelined, an experience that only deepened with time.

Two years after William's birth, the couple welcomed a second son, Prince Harry, on September 15, 1984.

Diana later told friends she hoped another child might heal their fractured relationship.

Royal biographer Katie Nicholl has written Diana believed she and Charles were "very, very close" in the weeks before Harry’s birth – the closest they would ever be.

Yet Charles reportedly expressed disappointment Harry was not a girl, saying: "Oh God, it's a boy. And he's even got red hair."

Diana's mother, Frances Shand Kydd, was said to have rebuked him sharply at Harry's christening, telling the Prince of Wales he should be grateful to have a healthy baby.

Diana later reflected Charles "put the shutters down" after being challenged. By the time Diana spoke openly to Morton, she said the humiliation she felt at William's christening symbolized the wider loneliness of her role.

"Those feelings of being left out at William's christening stayed with Diana until her death," another insider said. "For Diana, what should have been a celebration of her first child instead drove home the sense that she didn't count."