The writer seems to be an old woman. She describes the psychology of two old women living alone near the beach. They are trying to resist to becoming old and to forgetting things. They remember what their father had done to them; they know they are old and inclined to depend on their older brother.
I myself am a 78-year-old man and therefore, I can understand what they are doing. The writer seems to be describing what I am thinking about.
Well developed with nice conversations.