OK, a couple of thoughts:
1. I don't care about constitutional precedent or any of that stuff but, I dislike Charles for being a dickhead and not marrying Camilla in the first place. It would have saved two lives and a lot of grief...
2. Diana was not a 'media whore' as you so quaintly put it - the media hounded her constantly and persistantly up to and including the moment she and Dodi were killed by that drunk chauffeur.
3. You may think the government has the power, but the armed forces swear allegiance the monarch, and after each election the new Prime Minister has to ask permission to form the new government....
So I offer this scenario: The Queen refuses to allow formation of parliament and on a public broadcast calls all her people and armed forces to join her in making a new form of democracy - how many people would be on her side? (bearing in mind she is pretty much guaranteed the army, navy, and air force)
Or put another way: Your country? or a bunch of politicians?