"I am sitting here at my desk today in October," she writes, "longing for someone to hug me and encourage me to keep strong and hold my head high. This particular phase in my life is the most dangerous _ X is planning 'an accident' in my car, brake failure and serious head injury in order to make the path clear for Charles to marry."
Diana's prediction of her own death means nothing. She wrote all sorts of nonsense all the time. Charles isn't especially eager to be king, and no one including his mother really wants to see him on the throne. So who would have a stake in eliminating Diana just so he could marry without giving up his place in line? No one. The House of Windsor survived Wallis Simpson and Eddie VIII's pro-Nazi leanings, it certainly wouldn't be all that worried about the no longer royal Diana's dalliance with a Muslim. (Even if she married him, how long could it have lasted?)
And the TRUTH must be always protected by a Bodyguard of Lies .... Remember Hess!
I always thought X referred to Prince Phillip. But...I don't think she died in a set-up, I think it was an accident. I think she may have been afraid of Charles' father though.