Speaking for myself, I went to every party (invited or not) with my group of friends when we were 18. In the mid twenties we went to almost every party we were

Speaking for myself, I went to every party (invited or not) with my group of friends when we were 18. In the mid twenties we went to almost every party we were invited to. By the early 30s, we all moved to separate places far away abroad. Me and my girlfriend went to a few parties by colleagues of mine at our new country of residence, and they were nice but not really interesting (too many kids, more like family events). By now, late 40s and early 50s, nobody organizes a party and I don't want to go to a party anyway. They're boring and I'd regret drinking too much the next day, and if you don't drink alcohol, they're even more boring. So there's that. It was a gradual process. Now if we lived in Beverly Hills and had many acquaintances, I'd probably go to parties. But I'm not working in showbiz, I'm working in academia and unfortunately most of my colleagues are not very interesting personalities.