Camilla, once known as Camilla Parker Bowles, never anticipated taking on the title of "Queen Camilla." Yet, on May 6, the 75-year-old will be officially crowned Queen alongside her husband, King Charles, during his historic coronation.

"Given that she never thought about becoming Queen throughout most of her life, she's handling it remarkably well," says Christopher Wilson, a royal biographer and author of A Greater Love, speaking to PEOPLE in this week's issue. "Being constantly in the spotlight at this age is an enormous challenge, but she's resilient and can handle it."

Camilla and Charles first met in 1970 through mutual friend Lucia Santa Cruz, and the two shared an undeniable connection. However, Charles was urged to find a virginal bride, prompting Camilla to marry army officer Andrew Parker Bowles while Charles wed Princess Diana. Nevertheless, their love affair persisted.

Following Princess Diana's well-known declaration that "there were three of us in the marriage," Camilla Parker Bowles was labeled "the most hated woman in Britain" by the press. After the divorce of Prince Charles and Diana in 1996 and Diana's tragic death in 1997, Charles' staff worked diligently to repair Camilla's image as the "other woman."

By 2005, the couple felt confident enough to marry amid shifting public opinion, and they recently celebrated their 18th wedding anniversary.

A source close to the royal household tells PEOPLE in this week's issue, "She's quite determined," adding, "She endured a lot to be by his side." Royal photographer Arthur Edwards, who has covered the royals for The Sun for 45 years, notes that Camilla's warmth and witty humor consistently bring out the best in Charles.

Edwards shares with PEOPLE, "She never lost her common touch," and continues, "She makes him laugh. When something triggers them, you see them just laughing together. They do things with such enthusiasm."

Camilla's unwavering support for Charles and her zeal for her duties motivated Queen Elizabeth's final Accession Day message, in which she expressed her "sincere wish" for Camilla to be recognized as Queen Consort when Charles ascended to the throne. However, the Queen, a deeply religious woman and head of the Church of England, had previously grappled with Camilla's status as a divorcee and the nature of her relationship with her eldest son.

Once their marriage was approved, Camilla was welcomed at royal events. Over the years, she and the Queen bonded over their shared love of country life, and the monarch appreciated Camilla's commitment to her royal duties.

Camilla stood by her husband following the death of his mother in September 2022 and is now prepared to join him as Queen on May 6.

Wilson tells PEOPLE, "They function well as a team. It's impressive." He continues, "Her presence gives him reassurance. Despite all the grandeur of majesty, it's cold and lonely at the top, and her comforting presence is evident."