My family "bar hopped" after the dinner. We did a 30 minute reception and then had dinner at Barefoot by the Sea. They didn't kick us out after our 30 minute reception was up. The waiters left but we had everything we needed. I'm assuming it will be the same way for you if you choose to do a formal dinner. So I'm assuming you can stay at the dinner site if you want.
After we ate and changed cloths (around 9 pm by that time), we met our families for a quick drink. We started at the patio by the Irish pub (sorry- i forget the name). My husband and I left then. I think the rest of the bunch went to the Turtle bar, that was their favorite place all week. I've also seen pictures of them doing karaoke at the night club and it looks like they were having way too much fun.
So you should be find after the wedding finding plenty of stuff to do or not too- you can just grab a couple drinks and relax by the pool or on the beach too.
PM me if you have any other questions. Good luck!