Douse the queen of england personally read her letters?

I went on the official website of the english monarchy and it gave an address to were you can write letters to the queen of england herself. i was wondering if anyone knew if the queen herself personally reads the letters she receives, or at least is informed of what they say? or douse one of her administrators simply pose as the queen and take care of whatever the letter is re guarding, and the queen herself does not even know about them?