Black-Eyed Susans by Julia Heaberlin

Just finished another Thriller.  It starts with the main Character Tessa present day and then flashs back to a teenage Tessie.  Enduring a traumatic event, it unfolds into a nightmarish horror story.  The author writes a cliffhanger at the end of the chapter then makes you wait for the answers after the flashback.  Genius!  It kept my attention for sure!