At the beginning of the novel, Pi is free to pursue self-actualization; you see him doing this as he pursues his religious interests. It is only when your other needs are met (physical, safety, belonging, and esteem) that you can pursue achieving your potential, or actualization. He is provided for, he is safe, he feels like he belongs with his family and peers, and fought hard to gain esteem through others. Once he had those aspects in the motivational pyramid, he could pursue his hobbies and interests.
However, the shipwreck changes everything. All of a sudden, Pi is plummetted from the "self-actualization" level back down to the physical level, and safety level. In order to survive on the lifeboat, he needs food, shelter and water (physical needs), and to remain safe from predators on the boat (safety). He spends a good portion of his first few days on the boat establishing those areas. He establishes himself as the alpha male in order to ensure safety. The rest of his journey focuses on securing food, water and shelter, and maintaining his safety. Survival in harsh situations doesn't leave room for whining that you aren't accepted, or that you can't scrapbook anymore; everything is focused on the bottom two levels of Maslow's Hierarchy of Needs.
Pi's entire ocean journey is spent staying alive and safe. Note how religion is rarely referred to as he is on the boat; he just doesn't have time or motivation for that anymore when he is trying not to starve to death. I hope that those thoughts helped; good luck!