At a pub, you want to “catch up” with a friend whom you rarely see. A colleague asks to join you. Do you explain you’d rather be alone?
I don’t see a dilemma here. I might suggest to the colleague some other time would be better as I’m catching up with a friend, but I wouldn’t see any harm in asking the friend if this person could join us..
But it would depend on the colleague. If this was someone I knew who was of similar personality and humour as my old friend, it’d be natural to introduce them because I know they’d hit it off instantly. If this colleague was someone I rarely speak to anyway and wouldn’t go out for drinks with regardless, then maybe I’d pull the “leave us alone” gambit, albeit as politely as possible. It’s rude beyond rude to assume an open invitation exists.
This has always been a problem for me, going back to grade school. I never assumed that “we” included me. I wanted to be asked to join in excursions or evenings out, even if it wasn’t likely I’d be able or willing to go out. I wasn’t going to invite myself and be a third wheel, or fifth wheel or whatever. I could have asked to join them anytime, but then I’d never be sure if the “yeah, sure” was a sincere one as in “yeah, we really want you to come along because you’re cool and fun” or more like “now that you’ve noticed we have plans, I guess we can include you even though we don’t really want you around harshing our buzz…”
Or whatever would have been the lingo slang at the time. (It was the early nineties. What was cool then?)
It got better once I hit university, though. I struck it lucky with friends in my dorm. Sometimes it was between suite-mates, and other times it was just friends from various floors but regardless, we could join forces or split up in a myriad of ways without anyone feeling like they’d missed out on an experience. Nobody ever felt left out or left behind. It was a nice bunch. I’ve kept in slight touch with several of them, thanks to Facebook. A few I’ve lost track with completely but so it goes. There are a few I wouldn’t mind tracking down so I could perhaps have this pub experience with them but ah well. It’s been said life is a river…