And I think people are terribly harsh and unfair about the "Kate following William to St Andrews " thing.
I really thought I read that his choice of Uni was changed at the last minute (I remember that at the time) so there was no chance of people applying just to be there with him.
But, supposing I am wrong, or that Kate had met him beforehand and was privy to his secret plans . . . why does that mean she was trying to marry him? I expect she met him, liked him, fancied him, talked about Uni plans with him and thought "Wow, wouldn't it be fun to hang out with him at University! Might get invited to the palace, ha ha, how cool would that be?" They were friends for ages, sharing a flat and going out with other people, before getting together - think Monica and Chandler.
If she was really desperate to marry William from the off she probably wouldn't have gone out with anyone at University in an attempt to look "pure". 
I know quite a few of my friends have spent years in relationships waiting for "the man" to commit to them. It's not uncommon at all. None of these men were princes, particularly rich or massive catches. They just happened to be men that my friends loved and who were a bit slower to settle down than my friends would have liked. Sometimes it has had a happy ending, sometimes not. Hopefully with Kate and William it will.