The girl who this is based on actually came to speak at my high school, way back in the day. She seemed like a total basket case to me, and nothing like the girl who portrays her in the movie. At the time, she was in her mid to late twenties, dressed and spoke in a very tomboyish juvenile sort of way, and kind of seemed like someone who psychologically had never left high school. She even admitted herself that when she first started doing public talks, which was part of her community service, many people thought she seemed too unstable to do it.
Not a particularly effective movie in my opinion, because it seems to gloss over a troubled and erratic personality type that led to such a great deal of self destruction, and attempts to reduce and condense it into a couple month period after the accident, in turn making most of the turmoil appear to be a reaction rather than the cause.
The real life Lizzie went on about her alcoholism, how she would lie cheat and steal to get what she wanted, how she would often steal money from her mother, knew what she was doing was wrong, and hated herself for doing it, but was in a vicious cycle of self destruction, where being in that place was too normalizing for her to do anything else. Kind of someone who's life was destined to be a long painful drawn out mia culpa.
Mostly, she garnered a fairly positive reaction from the kids at the presentation. In my day, it was very popular, and probably still is, for school administrations to try to shock kids into behaving in accordance with whatever the present mode of choice happens to be. Is unleashing complete basket cases who use kids as their own personal mode of catharsis a productive way to teach them reason? Who knows, but being able to postulate on all of this now as a result, sure is fun.