I don't think I knew that much about her "rebellion" until after she was gone. She and I had our first children at about the same time, she married not too long after I married, there were parallels (as everyone else is saying) in her life and my life. I was embarking on a career where I had to do a lot of speaking in public, I was shy, I had far less of a sense of style. I never developed the easy manner she had with children and people she didn't know, but I learned from watching her.
I also could see that her marriage seemed less than ideal (mine was not the right marriage either) and we ended up divorcing at around the same time. I'm sure that my ex's family would have had plenty of unpleasant things to say about me (as they were never accepting of me in the first place and I could never please them - nor did I see pleasing them as one of my main goals in life, as it would have had to be, from their point of view).
Then, we were both single parents together - she with two boys, me with two girls. That's when I read the Morton book and began to see how painful, psychologically, her life in the palace had been. I'd had my own struggles with depression - but once I divorced, those evaporated almost magically. So she and I made youthful decisions we lived to regret, and I had great empathy for her struggles with body image, food, etc. I didn't know a single American woman in the late 80's to mid 90's who didn't admire her and relate to her in her struggles.
I didn't realize at the time how much the royal family was struggling with her, against her, or that the Queen had basically decreed the divorce. It just seemed inevitable - and from my point of view, mostly so that Charles could be happy with Camilla and be out in the open with that relationship.
She was a vibrant modern woman who ended up having her whole life exposed to the world (and her death), I don't think it's too sentimental to say that many of us loved her and always will, just as if she were a member of our own families (I know less about some cousins than I do about Diana, that's for sure).