I am also a writer. I am currently working on a novel and have run into the same problems you seem to be having...I completely agree with what everyone here is saying....I also have something to add to it..A friend of mine, who read my book(well whats completed of it), told me something and it made me think and as critical as it sounds or as bad I kind of see some truth within it...He told me that most people who write fiction tend to base characters on people they themselves would like to be, and the settings tend to be places you think would be your personal Utopia(sort of speak) So... If you think that things are sounding familiar to you ,as in things you've read before, you probably subconciously are drawing from other works that you find appealing to you...I hope that helps....I know it was long winded....
It took awhile for me to figure out what I was doing but once I figured it out I had no problem.
Good Luck with your writing....
Just don't forget everything you write is yours whether or not it sounds familiar....(unless you deliberately copy

)
_________________
Formerly Eruwaedhiel
[font=fantasy]Married To Draco Malfoy 9/11/07[/font]
Thnx Aerlinn & timtimtimtim 4 banner