I think she had the most to loose. If Diana had wanted, she could have stayed married to Charles indefinately. He would never have divorced her if she hadn't given the Panorama interview. She was a beautiful woman with charisma - always able to find supporters, even though she was not able to keep real friendships.
Camilla OTOH was in a very delicate position when it comes to society. She is not of such a superior birth that she could have dared not to care - not a Lady Jane Wellesly who famously said she need not marry a title, she was born with one! Then when her husband divorced her, she was just an ordinary Ex-officer's wife. Then she lost a lot of money with Lloyds... So she was not in a good position - and was heavily vilified in the media and by Diana's supporters.
She only had two things going for her: Charles' unwavering support, respect and love and her own ability to make real friends, long-time friends, loyal friends.
What we experience today is the real thing: an elderly lady, not very beautiful, not very healthy, not very educated, but with a sunny nature, genuine compassion, steady loyality, personal dignity and the ability to give others the feeling they are special.
That's what the media is forced to show us today because even as they try hard, they can't come up with negative things and time's definately on her side. Those who remember Diana age with Camilla - and view tends to change over time. What once was the story of a betrayed innocent and an experienced witch is today (thanks to years and years of reporting) the story of a man who was married to a beautiful but spoilt princess who chose the ordinary looking "best buddy"-lady in the end. Isn't that what we all dream off, now that we reached a certain age? When we read about the "new love" of this socialite playgirl and the new, younger wife of that freshly divorced Mr. Multi-Millionaire - isn't it much nicer to read about Britain's future queen who is adored by the future king, called my "Darling wife" and treated not only with courtesy but with genuine affection?