An Audience of Chairs by Joan Clark

Mental illness has been Moranna MacKenzie's lifelong nemesis in this character-driven novel set in Cape Breton. She was just a child when her mother committed suicide. Years later, the loss of custody of Moranna's two daughters was due to her own instability. When Moranna learns that one of her daughters is to be married in Halifax, she is determined to finally see them again. 

The cover art on the Vintage trade paperback edition -- a folk art mermaid set against a background musical score -- ties in well with elements of the story. Moranna created a mermaid tale to entertain her girls when they were still with her; she carves folksy images of her Scottish ancestors to support herself; and Moranna performs concerts on a painted piano board every morning to an audience of chairs in her kitchen. The cover illustration also captures the whimsical, fun-loving nature of Moranna (when she isn't being contrary and self-absorbed).

There are lots of other interesting and well-rounded characters too. It's a powerful and uplifting story of redemption and family pride.