I don't remember the whole thing but something happens where there are people on an island but it's like there paradise and they don't other people coming to it and then a young boy joins they group (he's kind of blonde maybe 17ish) and falls in love with a girl in the tribe. They end up getting together. Then the boy had to go to the city place with the group leader to buy stuff and they end up having sex. Then they get back and the boys girlfriend finds out what happens and he leaves the group and fends for himself. He goes all feral and makes traps for people and stuff. And I'm pretty sure a map is involved somewhere in the movie. And there is a part where a few guys get attacked by a shark. Please help me!!

http://en.wikipedia.org/wiki/The_Beach_(film)

Maybe but I'm not sure on this one.

The more I read about the Beach I think it is the right movie.

Yes thank you!! With Leonardo dicaprio! :)))) thank you

Glad to help you, been awhile since I have seen the movie but it sounded very familiar when I read what you wrote.