Why was the Sue Dubois (Agnes Bruckner) in the hospital? **spoilers**

minor spoilers follow...


































Apologies in advance if this is a dumb question, but, does anyone know why the Sue Dubois (Agnes Bruckner) character was sent to a psychiatric hospital?

Maybe I missed it, but, as far as I could see she had a penchant for sex, in particular writing about sex and was simply a passenger in a car that crashed.

It was fairly obvious why the Dori Lawrence (Rachael Leigh Cook) character was receiving treatment...but unless I missed something, I didn't get why Sue Dubois was there. If having a penchant for sex is a symptomatic of mental illness, I know quite a few who should be in straight-jackets. If it was an attempt to portray the problems associated with nymphomania, fair enough, but, in that case it was a little bit clumsy and unclear that that was the reason.

don't get me wrong..I enjoyed the movie. It was witty in places and very engaging, but, I got the feeling that it could have been a classic so I suppose I'm sorta frustrated with a few things in the movie.