A Tale for the Time Being by Ruth Ozeki (Viking, 2013).
This novel has two different narrators. One is Nao, a teenage girl living in Japan in the early 2000’s, who spent most of her childhood in California and is having trouble re-adjusting to Japanese culture. This is not surprising as there is an appalling amount of bullying. The other is a Canadian novelist named Ruth, of Japanese heritage, who finds the girl’s diary (in a sealed plastic bag) washed up on the beach one day near her home in British Columbia. The story also involves Nao’s great-grandmother, a Buddhist monk, and her son who was a suicide bomber in World War II but left behind a diary as well. The details of Japanese culture are fascinating but the focus on suicide (both Nao and her father keep contemplating it) is rather morbid. Father and daughter do decide to live in the end though.