My MIL lived the final two years of her life in a skilled nursing facility. She entered with dementia and within a year it had worsened a great deal.
The place had both single and double rooms, furnished to make a certain level of privacy from one's roommate possible. Residents (never patients) were encouraged to personalize their space with things from home--bedspread or throw, pillows, pictures, TV, etc. (They'd blast those TVs if their hearing was failing.)
The huge majority of the patients were in wheelchairs, although not all of them could remember that they could not walk, so if they attempted to stand, they'd fall. (Hospitals can legally restrain patients to their chairs, but nursing homes here cannot.) Falls from wheelchairs and beds were common, usually with only minor injuries, but once in a while someone would break a hip. For non-ambulatory patients who insisted on getting out of bed, the bed frame was removed, the box springs and mattress directly on the floor, so they had a shorter distance to fall.
Each room had its own bathroom. The floors were tile. The lighting was overhead fluorescent. The rooms were painted in pastels with a wallpaper border near the ceiling.
Both the nurses and the aides had a high rate of turnover, so Mom was often being cared for by a stranger. Few patients stayed in their rooms all day. Most often they were moved to common areas where the staff could watch over them more easily, usually ringing the nurses' station or in the dining area. (Where many could no longer feed themselves and were patiently fed by staff. The food was decent, too.) Music dating to the era of their young adulthood was often played on the sound system.
Only those whose dementia care required a high ratio of staff to patient were in separate units. Mom was mainstreamed with others. Those who did not have some level of dementia were very, very few. People sat in their wheelchairs in groups,their faces expressionless, not interacting, unresponsive to the music, not interested in the next activity or meal or anything else. The one thing which drew the most response in those with the most damage was visiting dogs. The last time I saw Mom smile was with a very nice Schnauzer.
Your character may have good days in which he knows who's visiting him and that they're friends, but he may have days where he's sad, confused, scared, unsure where he is or why they won't let him leave and cannot recognize anyone, and days when he's absolutely blank and empty, as if his brain no longer thought at all. That middle group break your heart.
You know, this is something that some real life experience could really help. Call the closest nursing home and ask if they have a patient with dementia who has not had a visitor in too long, and if it's all right if you stop by to chat about whatever his/her interests are. There are people who would be glad to see anybody who brought a smile and listened to them.
Maryn, able to discuss long after the fact