Dana - I totally sympathise. I semi-retired two years ago and whilst I have done lots of work of various types since, it took me this long to realise that what I missed was the camaraderie, the continuity of seeing same people and having a routine. Now I often don't see anyone but my OH all day [and he is out for most of it] and have to admit to overwhelming loneliness. I think this is what is causing me health anxiety as I have nothing else to think about.
I have applied for voluntary work one day a week, started yoga and piloga but really need somewhere to meet people.
It never occurred to me that I would feel like this - I used to long for p and q, but I suppose you only appreciate something when it isn't all day every day with no alternative.
It's a bugger, isn't it? But try volunteering, there will be a local volunteers bureau somewhere near you.