Okay, I'm going to toss my two cents in on the Diana issue for now and come back to the greater issue of the Queen and abdications later.
The BRF definitely has it's soap opera moments, and Diana definitely embraced them. I don't think she brought them to the family, though. Every family, whether royal or commoner, famous or not, has it's soap opera moments. The BRF ones just happen to be more notorious (the same can be said of other monarchies as well). These soap opera moments did not start with Diana, nor do they end there. I mean... God, this is a family that had the Conquest, the War of the Roses, Henry VIII, the Glorious Revolution, George III and his sibling, George III's children and the race for the her, Queen Victoria blaming Prince Albert Edward for the death of her husband, the Duke and Duchess of Windsor, Princess Margaret, Fergie, and so on. All of these have there soap opera moments (some just dilute due to the time in which they happened).
Diana did not introduce soap opera to the family, she just took advantage of the press and made the soap opera work in her favour - and ultimately she became this tragic figure who was destroyed by the press and the soap. She brought as much harm to the institute of the family and the family itself as they brought to her - and she brought good as well. As much as we may resent (or cherish) Diana for what she did, in a lot of ways she brought the family into modernity and in a lot of ways since then the family has chosen what aspects of her legacy they want to be involved in, and what aspects they don't want to continue to use.