I'm writing as someone who was fairly marginalised as a child for a number of reasons
I can think of countless examples in my childhood and youth where I was in situations where I was "forced " into socialising by adults who would insist others spent time with me and it was like hell.
They had no interest in me not I in them and I found the whole situation to be humiliating. Even worse - I ended up with low self esteem due to feeling i was being foisted where I wasn't wanted.
I once visited a family acquaintance and she suggested i visit London with her university student daughter so we could "bond" . I spent the day basically walking behind her daughter whilst I was ignored with no acknowledgement of my presence and the daughter played on her phone .
The thing is I myself didn't actually care - I'm naturally happy with myself and an introvert at heart and I've attracted loyal people who like me for ME as I get older. I'm career driven as an adult in a mega cool job pathway so that's me done.
But it was the idea that I "had" to fit in that did the damage . In my 20s i felt I couldn't just be myself and I was always wasting time with losers or people I had nothing in common with who had to be "bribed " to like me or spend time with me.
Rather than just now thinking "meh" and being more concerned about my own goals and involved hobbies.
Like pps said you need to take a step back and chill out a bit. It's easy to have some picture perfect idea of how your sons social life "should look like" . But just as grown women don't all have a group of cocktail loving "besties" teenage boys don't need a group like the Inbetweeners (in fact If you watch the Inbetweeners you'll see what a hideous lot they are ☺). Your son WILL pick up on your emotions and that's not fair on him.
Loneliness is the human condition - we all feel it sometimes . The super cool Duchess of Sussex commented on how she had years as an actress just working and not making any friends)
Maybe I'm being a bit middle class here but I'd value personal development over "hanging out" with friends
Looking back on my teenage years the things that stuck with me are grades and sports and (although I'm catching up now ) I wish I'd stuck with lifelong things like language learning rather than get bogged down in social politics over whether I had a list of people to go for a birthday tea with .