@ageingdisgracefully, agreed. I was almost exactly the same age as Diana. I was not a Royal-watcher by any means, but I'd been dimly aware for years and years that there was a lot of speculation in the press and in sections of the public about who Prince Charles would marry. It was of course taken for granted that the heir to the throne would marry and have children to secure the succession. (What a life! What a system! But that's for another thread ...)
It was also unquestioned at the time that he didn't have a free choice of who to marry. He would have to marry someone from the right background. A young woman from another Protestant European royal family would have fitted the bill, but there weren't many of the right age who were still single. The other acceptable option was to marry a young woman from a British aristocratic family, which was of course what George VI had done, and that had worked out well.
Also, even though the Abdication was a generation ago, it was still casting a long shadow. The idea that Charles could marry a divorced woman, or even a woman known to be 'experienced', was out of the question. In this, of course, the Royal Family and its advisers were totally out of step with the rest of UK society, which had changed massively in the years since the war, especially in the 1960s and 1970s. I would have had no problem with him marrying who he wanted, and I'm sure a large section of the UK public would have accepted it too, but the Establishment wasn't going to risk it.
It was therefore obvious even to me that when Charles married, it was very likely to be an arranged marriage in all but name, and so it proved. It was perfectly obvious from the media coverage of the time that he was a lot less enthusiastic than Diana, and they seemed to have very little in common. If Diana had been a different sort of person, it might still have worked, if she'd been prepared to do as women of her class had done from time immemorial and turned a blind eye to her husband's affairs. Grim, but pragmatic. Her role was to produce the heir and spare (eurgh) with no doubts about their paternity (eurgh eurgh) and then as long as she was discreet she could have done what she liked. But she wasn't that sort of person. All very sad, for everyone involved. But a long time ago. I'm glad Charles and Camilla are happy together now.