Some members did not like what Diana DID-- air personal problems to the tabloid press. Then, there was a family member who just did not have anything in common with Diana, Anne.
Diana did do things wrong. She aired private problems to the public by helping Andrew Morton write Diana:Her True Story. Diana also worked with tabloids ,like the Daily Mail's Richard Kay, to spread her side of stories to the public. She would let paparazzi know where she would be, during off-time, and then complain about their following her about.
And, knowing about her own popularity, Diana decided to try out a new hairstyle when she accompanied the Queen to opening of Parliament. The important news for opening is the government speech, but it was Diana's hairstyle that made the front pages. She upstaged a monarch with something so trivial as a hairstyle.
Diana used the press to make herself look better than the other royals. She would help plant stories to make herself look the victim while painting Charles as a cold, unfeeling villain.
You only know the public Diana, it seems, since you asked this question. Diana was not a saint. She had difficulties in her private life that made her hard to bear at times. She was mercurial, temperamental, possessive, jealous, and unprepared for her role in the royal family, yet she was able to do a good job reaching out through her charitable works. Diana was not a perfect person, but she was able to do some good, raise two fine boys. But, Diana and Charles both bear blame for the failure of their marriage. They both did not have what it took to support one another through trying and difficult times.
Diana was given books to read about the lives of other consorts and monarchs, but she believed she already knew what it took--she was wrong. She was very young and inexperienced in the ways of the world. Charles ended his affair with Camilla by the time of the wedding, but Diana was jealous and kept accusing Charles of having an affair even when he was not. She wanted to be the center of Charles' attention all of the time, not a realistic thing to want.
For a more complete look at who Diana, Princess of Wales really was, you meed to read biographies that tell the story about the entire person, warts and all.
The Diana Chronicles by Tina Brown
Ever After: Diana and the Life She Led by Anne Edwards
Diana by Sarah Bradford
Diana: In Search of Herself by Sally Bedell Smith-- just disregard any attempts in diagnosing Diana with a personality disorder because only a psychiatrist actively treating a patient can do so; the author's use of one psychiatrist's opinion on what he read about Diana's behavior is not a diagnosis since he never met or treated her.
Diana: In Private by Lady Colin Campbell
Charles and Diana by Ralph G. Martin
Royal Blood Feud by James Whitaker is about the contentious separation through the eyes of the press.