You know, I felt like this after my only daughter grew up and moved away. (I'm divorced.) I missed holding her, sleeping with her in her bed on occasion, literally missed brushing her hair. It's a kind of sensory deprivation.

I think older folks must experience this, too. After my father died, my mother enjoyed going to the chiropractor. She needed to go due to health issues but I think it also fulfilled her need for touch.