As I've gotten older I've become more and more picky about who I want to spend time with. It used to be, when I was a lot younger, that I would be pretty indiscriminate: as long as someone wanted to spend time with me, and they were nice enough, and we could find something to do together that we enjoyed, like watching a movie, playing a game, or just hang out and talk about something (usually meaningless), that would…
What do you mean by this, specifically? I've wrestled with the idea of finding people I have more "in common with," but I've ended up at a place where I think the idea of "best friends" is kind of an overblown myth, or at least it's a LOT rarer than people think it is. What's the fun in hanging out with someone who's the same as you, anyway?
I'm come to realize that, while I tend to think I'm losing touch with old friends because "we don't have a lot in common anymore," it's far more often just because one or both of us is being a shitty friend and the relationship isn't giving enough satisfaction in return to continue investing in maintaining it for one or both parties.
>how rarely we talked about or did anything that was really meaningful for me
But really, if you always did "meaningful" things and always had "meaningful" conversations with your friends, then nothing would actually stand out as "meaningful." Maybe there are other reasons to converse and hang out with people than finding deep meaning in everything. Most people seeking out that deeper "meaning" tend to have to find it for themselves, they don't just discover a perfect group of like-minded individuals who can evoke the meaning of life from their deep, intellectual conversations with each other.
>sometimes I notice some couples or groups of friends around me, having fun, laughing together, and it bothers me
I think this is sort of a social darwinism version of the imposter syndrome. It seems so easy when you see a group of people laughing together. It seems like they just effortlessly entertain each other, but nobody sees the inner workings behind the scenes. Nobody sees the fact that Jenny secretly hates Stacy, but hides it because the group is fun to hang out with and Stacy is always there, or that Steve is dating Brian's ex and Brian says it's fine but really secretly hates it, etc...
This idea where you see couples or groups of people who just seem to effortlessly get along, and it seems like they aren't even trying is totally false. Sure, there are people for whom social skills come far more naturally, but relationships of any kind take effort by both parties to maintain and grow.