As I discovered with my wife, there are many reasons why people stop eating and drinking. It must be almost impossible for staff in a NH to tackle the underlying causes, as it would take too much time with each patient. A familiar environment helps. As for communication, one does not require speech, there's sight, sound, taste, smell and touch. Familiar faces, places, sounds, tastes and smell can revive happy childhood memories of a time and place. A loving touch requires no words as dogs can show.
We moved a way from my wife's home town when we married. I made a point of phoning her sisters in Co. Durham from time to time, and asked them to speak to her, in order she could listen to the Geordie accent of her youth. It was quiet a revelation to observe her face as she listened on the phone.
The one overriding fact I'm pleased with is, that I took no notice of the 'experts' when it came to solving and dealing with the underlying causes of her refusal to drink and eat. When I first fed her, hours later the meal shot back up. I wondered why that was? There were two reasons.
It's now time I was moving on with my life. It's often said 'one size does not fit all, we are all different'. Yet the same approach is preached time and again and followed with many of the problems encountered with Alzheimer's patients.
I wish you well.