Nicest way to tell a jam group I don’t feel like playing w them anymore?

This is a little embarrassing to ask reddit for advice on, but it’s 3:30 right now and I’m supposed to head downtown for a practice at 8 with this punk jam group I’ve met up with a handful of times now. I’ll spare the details and say, it’s 40+ minutes both ways for me for what adds up to an hour or so of practice every week and we miss plenty of weeks, we pay $40 a month each for a practice space I don’t use for anything else, and I’m just finding myself kinda dreading it, the vibes are weird and it just turns into a hangout every time.

I really REALLY don’t ever want to be that guy that cancels the day of because I don’t feel like it, but I feel like if I go I’ll just be a pushover and say “see ya next week” again. Any thoughts or words of wisdom for me?

— UPDATE: welp! it’s been done! i sent a couple texts to the exact tune of what i’ve already said, and i haven’t heard back yet, i feel shitty about it, but i’m happy for this one inch closer to feeling like i’m being real with people (my lifelong dream).

if it’s not obvious from my post, i’m new at this. this year was the first time i started playing with other people. I landed a gigging band, got kicked out of it, bounced around some groups, have a promising thing im part of nearby, and this other group was feeling like a dead end, but i’ve never… DONE something about that before. So here i am doing something! Go me.

“Life teaches you how you should’ve lived it” -Louis CK, who i really fucked with before the Riyad thing, so i might just start quoting him anonymously now.