A big problem with all games, IRL and PbP, is burnout. I think there's a mental health lesson too, although it's one that I'm not qualified to teach because I don't know what works for you (and wouldn't it be weird if I said I did?), and I don't know what the nine-hells I'm talking about, but I think I know what works for
me.
I find that I feel happiest when I stay in my comfort zone. Comfort zones are comfortable—the clue was in the name (duh!). Outside them, it's uncomfortable. And there's nothing wrong with being comfortable when you want to relax. The rest of my life can be puzzling things out, but in my free time, I want something familiar.
So if I don't want to suffer burnout then I need to stay in my familiar places. For me, that's D&D 5e on the Forgotten Realms' Sword Coast, ideally with published modules. I run the same games over and over (e.g. I've run three Rime of the Frostmaiden and three Hellrider games) in the same Forgotten Realms locations (Icewind Dale, Waterdeep, Baldur's Gate, Elturel, Phandalin). As a player, I want to play on the Sword Coast. I don't mind playing with new people, in fact, I prefer that, but I don't like learning new rules, new lore, or new genres.
This was something that I had to learn about myself, and almost certainly doesn't apply to you. But I think there might still be a lesson. What kind of games make
you happy? What makes
you anxious and liable to burnout and ghost?
If you're comfortable playing only with the same friends, then don't let anyone tell you that you
should be playing with new members. You know you
'shoulds' better than anyone else. If people are pressuring you to GM or play a certain game, and it's not one that will bring you joy, it's fine to say no.
What's the lesson? Dunno. Perhaps audit the things that make you uncomfortable or anxious and don't do those things? That sounds simple and obvious, doesn't it? So why did I find it so hard to implement?
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Adam, like a therapist, but clueless