Juliet is forced to reveal some startling news to Jin when Sun threatens to move to Locke's camp. Meanwhile, Sayid and Desmond begin to get an idea of the freighter crew's mission when they meet the ship's captain.
Jin died on 22nd September 2004, as is written on his tombstone. The date is the day the very first episode of Lost aired, and represents the day the plane crashed on the island. This would imply that Sun has told the world that her husband died in the crash after she returned home.
Analysis
The Oceanic 6: Up to this episode, the following characters are revealed to be the sole survivors of the crash: Jack, Kate, Hurley, Sayid and Sun.