I have some very old friends and see them regularly, holidaying with some of them, eating out with others, and thanks to technology we keep in touch via emails and WhatsApp, so chat lots and plan lots.
Yes, friends from early marriage we used to see have drifted away, and yes, I'd hate to have regular dinner parties now! It's enough catering for friends who come to stay! I made the mistake of going to see an old school friend and her husband a year or so ago. We'd kept in touch via letters and Christmas cards over the years and the odd meet-ups when we were young marrieds and had children. Our children had grown up and I had since divorced, so much of the ground we knew had shifted over the years. She talked non stop about her life and family, didn't ask us anything, forgot OH's name and her husband didn't say a word, as usual. I'd completely forgotten how she could talk! It was almost a monologue. I am sure she used to be more fun though. We were so glad to get away.
I have not invited her to us. I didn't send a card last year either, but I'd had a cull of names in my address book anyway, since our house move. I feel quite bad about realising there is really nothing there, no reason to have her in my life any longer, or to even share news with her.
Water flows under the bridge. I have no idea why people want to reconnect (on Facebook, etc) with old school friends they haven't seen for 60 years.