The Glass Lake  by Maeve Binchy 
I’m sad that Maeve Binchy passed away in 2012. She has so many wonderful books and The Glass Lake is now one of my favorites. Set in 1950’s Ireland and London, The Glass Lake is classic Binchy. Kit McMahon’s mother, Helen, didn’t belong in the small Irish hamlet of Lough Glass. The troubled woman walked night after night along the shores of the serene lake. Then, when Kit was only 12, her mother disappeared one night. The mystery surrounding what happened to Helen will haunt the girl for years.