That is my point, I vote for candidate A, I DO NOT WANT candidate B to win, so I am f***ed if I am going to allow him anywhere near my vote in the event of my preference not winning. Sometimes you win, sometimes you lose, get over it, it happens.
Well that's fine for someone who, like you, wants one particular candidate and has absolutely no preference between all the other candidates. But that's not the case for most voters. A lot of people have a favourite candidate but also have an opinion on which of the other candidates they prefer. AV allows them to express that. The whole point of an election is to allow the public to express its collective opinion in the context of producing a parliament and government that are as far as possible both representative and stable. A system that better represents the views of voters would therefore be a good thing.