I have a lot of thoughts about this.
I really loved the beginning of the book. The details about what it's like serving the British royals are fascinating. How the castles are run, how the staff are trained and treated, is great stuff. You can tell that Burrell greatly respects the queen and the prince consort, and they treated him very well also. It was interesting seeing first impressions of Princess Diana joining the family, and what it was like for him to switch over to working for the Prince and Princess of Wales. Although he's respectful of Charles, it's pretty hard to hide the fact that the guy is kind of a tool, and always has been, and you can see how Burrell became very fond of the less uptight, more fun, Princess.
And then halfway through, things take a turn for the weird. Once Charles and Diana separate, he lets his freak flag fly, basically. He is so devoted to her, it's to the point of obsession. He admits several times that he was a crappy husband and father, because he spent so much time with Diana. He speaks about her as though she were a goddess, even while admitting that she could be rather capricious and even bitchy. Diana got mad at his wife and didn't speak to her for TWO YEARS even though she lived in a cottage on the princess's property. And did Paul attempt to step in and make peace? Of course not! If Diana hated his wife, well, that's just too bad for Maria, then. What the hell, man?
He started to get more and ingratiating and smug, constantly detailing how close his relationship with Diana became, how many gifts she gave him, how close he was to all her friends. I didn't figure out why until the end, because I didn't realize that he'd been taken to court (supposedly by the Royal Family, but actually by the Spencers), and accused of stealing from Diana's estate. The book is his attempt to set the record straight, but it's weird because it's almost two different books smashed together. One professes his innocence, the other is a tell-all about life in the palace.
Do I think he's innocent? Yes. Do I think he really was her right hand man, and one of her closest confidantes? Yes. Do I think, however, that he is a total basket case, still obsessed with her? Yes. Do I find it super tacky that he kept alluding to a secret only he knew, and would never tell? YES I DO. If you're the Princess's secret keeper, and you feel that confidence extends beyond her death, then stop freaking telling everyone in the world you've got a secret, and then being coy about it. Ugh.