I don't remember such scenes from university, maybe because I made actual friends then. Several of these will soon be visiting me! So it became easier to satisfy my desire for social interaction. The desire was still strong then, though.
When I moved to a different country things started to change. If you move to another place every few years, to somewhere you know nobody, and might even not speak the language, you learn to sort yourself out. And as I was moving to all these different places with lots to discover I started to shift from pursuing people to pursuing activities. If you move to a new place it offers new opportunities! And you don't have friends yet so you start to pursue them alone. Not all, of course; in Norway I did a lot of hiking, climbing, skiing, and sea kayaking with other people, but only after I'd made friends. In Plymouth I rather quickly joined the PCG (and later CMEC and DCRO), and in York the YCC. Here in Wales I have joined the Thursdaynighters and Clwb Mynydda Môn, and countless Welsh classes.
The thing is, once you start filling your life up with, say, mine exploring, running, climbing and learning Welsh, you get used to restricting yourself to that and nothing else. Another thing is that time runs out to do anything else. So a difference is that in the old days I spent a lot of time only socialising; these days I rarely ever do. If I see people now I am engaging in some activity with them, be it some outdoor pursuit of learning Welsh. Or walking the dog. If I now am in the pub, there is a ~0.95 chance that that is because I am having a private session with Jenny, my Welsh tutor. The only exception here is, I suppose, sometimes having dinner with Marjan and/or Jaco, or any consumption with Guy and/or Kate.
All the people that I see doing stuff might very well vanish from my life as soon as I stop doing that stuff. Not all, I hope! But the vast majority, I suspect. This sort of means I spend more time with acquaintances and less with friends. And it's fine! I am quite happy spending my weekends alone, doing chores, going for a run, or going for a hike. I also don't mind going to things like movies or weddings on my own. But not needing other people very much anymore does have its downside: as I am cramming my leisure time full of what pretty much is investment in myself (improving my health and fitness, improving my skills) there is little time left for other people. I'm turning into a growling loner! And that would be pushing things too far. Liaising with people is important. I now sometimes look back on the last few days and realise I should have been more social at several occasions. Oh dear. It is very, very good to be able to depend largely on yourself, but if you turn into some antisocial sod you've let it go too far! I need some recalibration I think.
Typical case of me being on a scamper on my own