Elena Gilbert was your average normal human girl living her average normal human life until the accident. Her parents car slipped off of Wickery Bridge and she should have died with them. Stefan Salvatore came into her life and saved her, not that she knew it at the time. Later, she met him on her day back at school and there was instantly chemistry. 

She found out about the vampires, the supernatural world and the lives of the Salvatore brothers: Stefan and Damon. Elena knew from the get go that she did not want to be a vampire, but one thing led to another and she was sent off of Wickery Bridge again and she died, but with Stefan's blood in her system. Freaked, she ran from the hospital, but was calmed down by Stefan eventually when he taught her to feed. 

Hating Stefan's diet, Elena was prone to sneaking human blood from the bloodbags in the basement. She wasn't a ripper fortunately, which worried Stefan once he found out what she was doing and it came to be that she had more control than either of them thought she would. There was worry that she would end up being Sired to Stefan since she had drank his blood, but since she didn't listen when he told her to drink animal blood, they realized that fortunately wasn't the case.

Elena does sometimes drink the animal stuff, but prefers bloodbags. She also does not end up getting linked to Bonnie, which is a relief to everyone involved.  

She eventually follows her mothers dream for her of becoming a writer. When she's not writing fantasy novels, she's working at the local hospital, something that she's also learned that she loves doing. If she can save even one person with her abilities or even the normal way, then it makes her feel like there's more to being a vampire after all.