The Thin Place by C.D. Major

This book is based on the fascinating history of Overtoun House and Bridge in Scotland. Since the 1950s the bridge has been nicknamed the dog suicide bridge for the over 600 incidents of dogs jumping off the bridge into the ravine below.  Of these over 50 dogs have died.  Explanations over the years range from an irresistible animal scent to the paranormal. 

Ava Brent is first introduced to the mystery when,  as a journalist,  she is assigned to cover the story. But everyone in town is reluctant to share any information,  fearing the strange atmosphere the house and grounds have over the town. Ava feels that same strange pull after her visit,  compelled to keep returning and digging into the mystery... to the point of obsession.  Soon,  the rest of her life is falling apart, sacrificed to her obsession, even her relationship with Fraser and the pregnancy they've longed for. Told in 3 timelines between Ava, a woman named Marion who married and became mistress of the estate,  and a sickly child named Constance whose bedroom overlooked the bridge,  the ending will leave you gasping. 

I didn't realize this was based on a true location until the explanation at the end.. so of course I then had to look up the history myself! I was dragged into this creepy mystery from the first description of Overtoun and unable to stop reading. I absolutely loved it!