"He himself was plumbing an unfathomable sea". How does the statement relate to Phatik state of mind in 'Homecoming'.

In the story, “The Homecoming”, Phatik who is the protagonist of the story is faced by many crossroads before he could reach home. The first experience of Phatik’s homecoming was when his younger brother was injured and ran home to tell his mother about the fight he was involved in. Though Phatik wanted to go home, he delays it because he knew that he would be punished for being involved in a scuffle. On his way he met his uncle Bhishamber who proposes to take him to Kolkata along with him so that he could get opportunities for better education. Phatik was very excited to go but that homecoming proved to be another disappointment. After going to Kolkata, he discovers that his aunt didn’t like his presence in their home and could never make a place in her heart despite of his attempts t please her. Eventually he misses his life and asks his uncle whether he could go back home. He asked him to wait until their vacations. He made an attempt to run away but was caught by two police officers who return him back to his uncle, this count his third homecoming. The fourth and the final homecoming is his death. He waits for his mother and when hi s wait is over, his condition becomes critical and he dies. This was the time when his mother showed him true love and care calling him darling.