Any theories as to why they broke up?

I think that this break up is a result of royal internvention. Prince Phillip and the Queen probably saw that they were getting closer and closer to marriage. In fact, the rumors of their engagement had increased over the months. It would be completely unacceptable for Wills, the top heir, to marry someone like Kate Middleton, so they told him to break it off.

I think she got a taste of what was to come with the constant harrassment and strain from paparazzi and decided it just was not worth it.

Maybe Prince William is actually every bit as annoyingly smug as he looks and she wised up to it and scarpered.

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Gradually decreasing the quality of my own obituary.

I really want Prince Harry to be king. I just love the idea of the King of England falling out of a bar in Soho surrounded by strippers.