1. Elena doesn't show as much care and concern for her "best friends" as they do for her. Every time shit happens to Elena, Bonnie and Caroline are there for her. In Season 3, she did nothing to comfort Bonnie about her break-up and she forgot about Caroline's birthday.
2. Elena is a manipulative bitch. Twice she got Damon to compel Jeremy. TWICE.
3. Elena plays on Damon's feelings. Despite being with Stefan, Elena constantly asks Damon "to be the better man" and expects Damon to comply "just because she's the one asking".
4. Elena is a Hitler. She tries to dictate Jeremy's life even though she's barely older than him. Interestingly, Elena isn't even Jeremy's blood sister.
5. Elena is a hypocrite. While it is perfectly fine for her to be running around with a vampire for boyfriend, she wants Jeremy to cut any connection with ghosts/spirits. Well, but before that happened, suddenly she wants the connection to the other world (ghosts/spirits) to be present so that she can save Stefan.