Miraval out in Austin bills itself as a wellness resort. It's all-inclusive in that it does include meals (when I stayed, the meals were VERY good), some activities (others have an upcharge), and you usually get some sort of credit towards spa services.
When I visited (pre-Covid) it was around $500/night. Idk what it is now, but since it is all-inclusive when it comes to meals and most activities, they do increase the nightly rate if there are two people in the room. Expect it to be double for two people.
With that said, the resort is lovely, is adults only, and the spa services are very good. I wouldn't spend a week there, but a couple of nights is great. Especially since you can arrive a little early and leave a little late to take advantage of the resort amenities (you just have to be out of your room).
Lake Austin Spa and Resort is a similar concept, but I believe it's even more pricey than Miraval. Miraval also has a resort in Arizona.