I read this too and I felt exactly the same as you: the writing style is very basic, and there's no 'second act' where the author comes to any kind of self-realisation or evolves.
It may be that we're looking at this through a modern lense where we're expecting that to happen, when really the whole thing is self-realistion, ie. she just wanted to shag rockstars and have a laugh, and therefore this book just wasn't for me. I found it all a bit grim in a way though, because to my mind most of the men in the book treated her like crap.
Would not recommend!