Here's another suggestion, consider a couple of nights on Koh Mai Thon, a small island off Phuket's southern coastline: Here's a bit from their web site, it'll give you an indication of what this island's all about. You could certainly arrange a secluded and wonderful dinner on the beach of this island - about as close as you can get to having a private island (with full facilities) in Thailand.

Islands in the open sea with accommodation: Koh Mai Thon – beautiful and up-market

This is a full-service resort occupying its own island, a rare advantage in this area. The accommodations here are first class, and the beach and surrounding waters are idyllic. If you want something very comfortable, on its own island, with few people around, it’s hard to beat this. The island is small, and there are not many places to go, so this is for those who want a truly relaxing, do-little holiday.

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