I'm not surprised at all, OP.
I saw this with three of my grandparents. Even if they still had living friends, they were all too depressed/ill/impaired/far away to visit.
My MIL is in a very long-drawn out Parkinson's, has reduced mobility, and even though she has all her wits about her, she can't talk very well and can never be sure how she's going to feel, physically, from hour to hour. Friend visits are not happening.