Here's an example of a book in which the supporting characters are more likeable than the main character. Cecily is spoiled, self-pitying, and at times churlish, but she does try to grow by the end of the book. As for me, I was wanting more of her college counselor, who clearly didn't take any of her shit or anyone else's. Why is it that writers often create secondary characters who steal the show? Why not structure a story about them?
Anyway, the pacing is excellent and there are some surprises, but ultimately this fell flat. Maybe it would have worked better as a series (and I think that's the first time I've said that, usually it's the other way around; a one-shot book being expanded into a series for $$).