The Sun, the Moon, and the Truth

The war is won but after years, rebuilding is still slow and tenuous.

Katara feels homeless. Everyone else has found a place for themselves after the war. Zuko is the Fire Lord. Aang is the Avatar restoring the Air Nomad nation. Toph has founded a metal bending school in the Earth Kingdom. Sokka has taken the lead beside their father in the Southern Water Tribe's rebuilding and modernization process.

It seems there's no place left that needs Katara.