Absolutely 100% agree @ssd Mid 50s here, and DC left home some 7-8 years ago. I CBA with anything really. I am done. Tired and weary and CBA!!! I rarely cook from scratch now, and tell DH if he wants anything fancy, or anything different, he can get it himself. I don't iron, I don't sew anything, I don't do anything I don't have to. I sometimes spend the day just reading and watching TV.
I was raised a Christian, and used to go to Church a couple of times a month, but stopped over lockdown because of covid. Then I realised how much I didn't miss it, how boring it had become, and how bigoted and judgy some people there were. So I couldn't be arsed to go back. Haven't been in a year now, despite all the snide little digs from people every time they see me, with the 'haven't seen YOU at Church for a while!' line. I just say 'no I haven't seen YOU either.' 
I can quite easily just see my 3 friends - who I have known for 20 to 40 years - just once every 3 months, I don't want or like or welcome visitors very often, and I even see my DC only once a month for a day (they live 25-30 miles away.) Extended family, brother and brother in law and cousins, we see twice a year. 3 times tops. I do speak with the DC most days on social media/whatsapp, but meet only once a month.
Can't even be arsed with pets anymore, and when my one remaining cat has gone (she is 16 now) that's it. No more. CBA with the responsibility. The pets were fine when the DC were at home, but since they've gone, fuck me the cat does mither and pester me! I have given 25 years to pets. ENOUGH now!
I WFH 22 hours a week, and that is enough. Luckily as I WFH I don't have to be arsed with mixing with people.
I CBA to take in packages for people as I don't want to have to spend half an hour 'chatting' to them when they pick up the package (or when I take it around to them if they CBA to come get it.) No parents or PILs left as they have all passed, so we have no elderly parents to look after thankfully.
I have spent many years raising kids, looking after parents, and looking after pets, hosting parties, (for me and DH AND for the DC,) having a couple of dozen people around sometimes, catering for them, and giving them drinks and entertaining them. Also, I had the neighbourhood's children around half the time, around for the first 12-15 years of the DC's lives, and their parents couldn't be arsed with them.
I used to be in hobby groups and socialise a lot more too in big groups. But now, just once a month at the pub is fine, and the occasional night out for a meal (5-6 times a year) with colleagues - mine or DH's. OR the DC or friends. I prefer to go OUT and meet, as I don't want to be entertaining people at my house.
Just CBA.
Glad it's not just me!