Are there any good-quality senior care centers in Red Hook?

Not right in Red Hook, but in the surrounding areas there are good-quality ones. Wells Manor in Rhinebeck provides subsidized housing for independent seniors, and is located ¼ mile from Northern Dutchess Hospital.
Hudson Valley Senior Residence in Kingston is an assisted living facility for those who don’t need nursing care, but may need assistance with certain daily things.
And finally, The Fountains at Millbrook provides both independent and assisted living. This is a very upscale place - bring money.