You said any ideas so I will ad our favourite place but it is not the Caribbean but the middle of the Atlantic Bermuda.

Not cheap unless you go in the 'winter' where it is cold when it is 18C (16 is 61F) so not great if you want water but a lot of history and very pleasant people.
The whole island is like a big resort.

Rooms are around half rate from Nov through March when we like to go but we are not beach people, just explore.

I often check the web cam at The Dockyard and do not think it is nearly as much fun there when 1 or 2 cruise ships are tied up unloading 4-5,000 people each.
When we visit there are only a few tourists around the ferry is seldom half full up top with almost none below unlike cruise ship season when it appears to be packed every time it leaves or returns.

Where ever you end up enjoy your special time and remember before long you will be looking at 40 or 50 year celebration.

BTW we do not drink much, if any, so do not get the inclusive deal just a meal plan.