I may go against the grain a little here, but I do think in some circumstances there is a bit of a dynamic change between friends in a group.
For instance, in my experience, most everyone in my social circle (now) is married or is coupled. I have a guy friend, we’ll call him G, who dated a girl, we’ll call her S, all through college and they were together for 5 years. During that time, I got to know S very well and I was extremely close with both of them. G was planning to propose to S, but didn’t when his family wouldn’t bless their marriage unless she converted to Lutheranism. S was like, “Uh, no thx, lolz” and they broke up. S has now dated other people and recently moved in with her current bf. G and S still talk and see each other at social events (with mutual college friends) and that shit is awkward.
Meanwhile, G has not dated ANYONE in the 2 years they have been broken up. He won’t go to bars, works strange hours voluntarily, and is just about up to his eyeballs with his singleness and lonliness. He is happy for us, but at the same time, he sometimes lashes out (he does not like my Fiance for some reason, and hasn’t the entire time we’ve been togeter, I have yet to figure that out) at people because he is unhappy with himself. He wallows……a lot. He feels behind. A lot.
A married couple friend of ours just had a baby, and G will have gone to 3 weddings within the same year by the time mine is over. I know he feels stagnant. He won’t take our advice on how to meet people and generally feels down about himself. No matter what we do to lift him up and help him, it’s just not enough.
So I do think there are things to be considered. I often feel bad when there is a gathering and it’s D&D, D&J, S&T, Me & Fiance….and G. = I know it’s the elephant in the room with him. It DOES make people feel sad sometimes, especially if they’re in G’s shoes. You DO have to kind of take a different approach with people in those situations. If they’re happy in their singleness, that’s one thing. But watching everyone around you have the life you thought you were going to have or wanted by now DOES affect things.
I have no real advice for you, OP, more just a word of empathy and understanding.