SOLVED. Book about an Uncle's secrets and a missing mother

[Amanda]

I cannot find the title and author of a book a remember reading within the last 5 years. I have only some basic fuzzy things lot points with some weird details from the book that stuck out for being really crazy! Basically a collage aged girl is in her hometown when a mentally handicapped girl she went to high school with is murdered. The main character takes a job working for her uncle (who's name may be Clay....) and he seems like a really great guy who helped raise her but he has some dark secrets including things about her mom who came to the area as a loner and did manual labor for some farmer. She at some point disappears or ran away after a confrontation with her husbands brother (who is the main characters uncle) who was in love with her in or near a cave. The uncle turns out to be coordinating a sex trafficking operation which is how the mentally handicapped girl was killed by the principal or vice principal of the local school who electrocuted her. That is all I can seem to remember....

[Amanda]

Solved--- The Weight of Blood