I'd call this an amoral film attempting to teach a "moral."
I didn't agree with some decisions made by the main character or the rest of the cast, but I could relate to her being surprised at herself making those decisions. And, like her, things have often worked out in my life in spite of mistakes I've made.
Speaking of relating, I'm sure my I've-had-my-fill-of-pretty-shiny-things-and-now-I'm-looking-for-someone-of-character Mr. Right is also just around the corner... ;)
Anyway, the movie portrayed promiscuity as something very laughable and insignificant and I'm almost surprised in retrospect that I didn't find it more offensive. Perhaps it's because I'm desensitized. Or perhaps it's because the production had a very melodramatic, stage-like feel (did I mention Amy Adams?) and I didn't take it seriously. It kept my interest....but...yeah...I probably won't be watching it again.