Being addicted to a series of books is good! I love when you're so into a certain series and the reading just flows and time doesn't matter. Plus, Twilight is only 4 (?) books and Harry Potter is only 7. You have a real problem when you get addicted to something like Sharpe or Discworld.
Best thing I ever got addicted to was Peter F. Hamilton's Night's Dawn trilogy. Trashy Sci-Fi Space Opera stuff, but these were three chunky fucking books totalling a million words (fair play to the lad, I've just written a thousand in a week.) It was a great three weeks, apart from the last book which my brother had dropped in the bath and was now twice the size - I got cramp in my thumb from t=reading the bugger.
I always consider myself a book addict, but I do know a proper one. A friend of my parents used to spend all of his family's money on books, to the extent that it really caused problems in the relationship and they had to reinforce the floors on the first floor so that the bookshelves wouldn't break through. Sadly, this is a true story that, in real life, has a happy ending. He spent more time going to the library.
I'm sorry if this random collection of stories makes little or no sense. I'm very very tired.