I second Grenada, easy to get to from the US meets most of your requirements, except maybe the shopping, no designer outlets or any of that. Kim and I have been out till the early hours of the morning, the only tourists drinking in a local rum shop and then walk 1/2 mile home along the main road without any concerns. You can also take the ferry to Carriacou for a couple days, it's a beautiful place to go if you just want to chill on the beach, not much else to do there

Drink all day at home, your friends worry about you; do it on vacation and they say "what a good time you're having". Save your friends needless worry, travel more!