My RP club has been going on for many years, which has the unfortunate effect of us getting older. Many members of my club have started to acquire something called a 'real life'. I'm not entirely sure what this, but it seems to involve some kind of long haired chesty variety of humanoid and sometimes small people running around. For some alien reason, club members seem to prioritize this over gaming sessions.

I am currently GMing multiple games, and I have the constant problem of my players phasing in & out of existence like a pack of blink dogs. What is the best way of running a game with a constantly unreliable group?

So far I tend to carry on with the game if a few members don't show, but avoid major plot points or big fights. I also try to throw in some side-quests, which seems to be a good way to slow the party down whilst keeping momentum going. This approach seems to mess up party xp though.