Sun is watching Jin on the beach where he is fishing (just for something different), she turns and heads off into the jungle. A little way in she stops and takes something out of her pocket. We see that its a Californian drivers license, and that it has a false name on it. She crouches down and starts digging a small hole into which she puts the license.
Just as Sun drops the license in to the hole, Michael appears, he’s calling out looking for Vincent. Michael asks Sun if she’s ok, and she glances down at the hole that she’d been digging. Michael bends down and picks up the license, and Sun starts to explain before Michael stops her and hand her the license. Sun then says that she was going to leave Jin, and start a new life in America, but she had changed her mind at the airport. This is another example of a last minute “change of plans” that resulted in one of the losties ending up on 815.
Michael reassures Sun that they will get off the island and everything will be alright, but Sun says that being on the island is her punishment, her destiny. She says that Jin is no longer the man that she fell in love with. They are just about to kiss when good ol’ Vincent appears to spoil the moment. Could have been worse though, what if it was Jin with his fishing spear.