Some of the finest resorts in the world are on St. Lucia. The beaches and the twin Pitons there are incredibly beautiful.
The Jade resort is high up on the side of the mountain, and each cabin comes with it's own private swimming pool. There are less expensive properties on the island if $1345 a night is too much.
I would suggest you go online and see what properties meet your budget. And I warn you there's a second St. Lucia in Africa that can get mixed up with the one you're looking for.
I've been to virtually every island in the Eastern and Western Caribbean and Bahamas. St. Lucia is my favorite island of them all.
If you need transportation, contact Cosol-Tours.com and ask for Yellowbird. He's the brother and just the nicest person and great tour guide.