"Emotionally bleak and miserable"
Sharp Objects is a good book, but one that is clearly not for me. It lacks two critical characteristics that I require to enjoy a story.
The first is likable characters. Nearly every major character is so deeply, fundamentally flawed that I could not relate to them nor care about them. If I don't have characters to root for, I cannot become fully emotionally invested in their plight.
Every bit as important is the overall emotional curve of the book. The entire book simply feels miserable. There are no moments of joy, happiness, or love that aren't wholly corrupted by their circumstance. Because of this, the darkness loses its edge - there's nothing to contrast the darkness to. It is dark, lonely, and bleak, from cover to cover (so to speak).
If these aspects do not turn you off from the book, you're in for a good if somewhat predictable mystery with a few twists and turns and with a peculiar focus on smells. Be forewarned though, if you look up what mental disorders the book deals with, you will have the book's mysteries solved before you're halfway through.