Take a look at Dorado Beach Ritz Carlton Reserve. It is not a Spa Resort but my boyfriend and I found the plunge pool rooms very refreshing. For your relaxation purposes I'd recommend the plunge pool rooms.

They have a traditional spa which I toured but did not take any treatments. I believe Machine Gun Kelly and Megan Fox got engaged in front of the spa building.

Again this is not a spa resort but I believe one can find their own level of relaxation here.