What is the author's style in the novel, Why We Broke Up?

The novel is in the form of a letter from Min to Ed. There are not definitive chapters in the novel, but there is some separation as it relates to the items that Min includes in the box she is returning to Ed. Each section ranges from 10 to 20 pages long. The chapters tell the story primarily in exposition and with some dialogue. The author injects his own voice and thoughts throughout the book, providing his opinions and feelings of the events unfolding in the novel. The narrator, Min, switches back and forth between the past and the present.