The Lilac Notebook

Holly Baranov is in the beginning stages of fast advancing Alzheimer's at 40. Unwilling to care for her, Holly's husband leaves her. While frightened to be on her own, Holly is relieved to be freed from the clutches of a controlling husband.
She moves out of her large home in the middle-class west end section of Montreal and into a small apartment near McGill University where she enrols in a poetry course in the hopes of stimulating her brain.
There she meets Kim Harris, a thirty-something beautiful but damaged law student and Amelia Rose, a twenty-year-old pole dancer in a seedy nightclub who wants nothing more than to graduate, teach high school, marry and raise a family. Both Kim and Amelia were victims of incest, though each see her perpetrator differently. Kim chose law so as to right the justice she was denied while Amelia is angry at the justice system for separating her from a flawed father who was nonetheless her whole world.
When Amelia is found strangled in her apartment, Holly becomes involved in the investigation, both as prime suspect and as a means to defend herself.
Detective Alice Vireovich and her rookie partner, Detective Dan Cardoni, currently investigating the murders of two middle aged men, are also tasked with investigating Amelia's murder: They come to believe all three murders may be linked because of a Van Gogh Starry Night postcard found at the scene of all three crimes.
Holly's health worsens quickly. She is transferred to a support facility. Along with her fading memory, Holly is also losing her ability to speak and write. She is uncertain whether she killed Amelia as her friend Kim, ex-husband Roy and the police suspect.
A niece (whom Holly doesn't recognize and whose motives she distrusts for suddenly wanting to help her) visits Holly regularly and reads Holly's notes about Amelia's investigation. This eventually leads the investigation away from her as they seem to implicate Kim.
Kim's law teacher at McGill agrees to take on the case pro bono, motivated by her interest in litigating whether damaging effects of childhood abuse pose the question whether murder can ever be justified in such cases.
The expanding investigation leads to more findings relating to the postcard found next to Amelia's body, bringing into view a surprising new suspect.