How does Kyung-Sook Shin use imagery in Please Look After Mom?

In Part III, it is important to note the language in which the author describes Father's return - specifically, with the summer/winter imagery. This can be seen as metaphorically reflecting Father's emotional state (i.e. having left in the "summer" of new love, returning in the "winter" of that love having worn out its welcome and/or the "winter" of shame). This is one of the very few instances in the narrative in which poetic language/imagery is utilized.