finished reading

This is one twisty domestic thriller!  It starts rather slowly but the ending left me with the best kind of WTF feeling!  I am still trying to figure out some of the final things.  The story is told in the dual narrative of Ruth, the unassuming mother, and Catherine, her daughter who thinks she knows everything about her mother.  It starts with Ruth's manipulative attempt at keeping Catherine from fulfilling her dream job.  But the layers unfold and more is revealed.  And then more is revealed.  And then WHAMMO!  The ambiguous ending is killing me!  

From the publisher:

Catherine Sterling thinks she knows her mother. Ruth Sterling is quiet, hardworking, and lives for her daughter. All her life, it's been just the two of them against the world. But now, Catherine is ready to spread her wings, move from home, and begin a new career. And Ruth Sterling will do anything to prevent that from happening.

Ruth Sterling thinks she knows her daughter. Catherine would never rebel, would never question anything about her mother's past or background. But when Ruth's desperate quest to keep her daughter by her side begins to reveal cracks in Ruth's carefully-constructed world, both mother and daughter begin a dance of deception.

#52bookclub prompt 33: an abrupt ending