OT: Non-Facebook group collaboration suggestions

Hi fellow Trisquelers,

I'm posting this in the Troll Hole because it's probably off-topic (but hopefully not troll-worthy).

I'm a member of a non-technical group, which is a part of a wider collective of groups, that uses Facebook groups and events for online collaboration. Obviously I find this concerning. I did create a Facebook account in order to participate, although my participation is quite minimal, due to privacy concerns on using Facebook.

My question is: do any of you participate in non-technical groups that have this problem, and is there a solution? A few potential solutions might include mailing lists, forums, or federated social networks like Friendica/Diaspora/GNU Social. How do you deal with public events, especially among the younger generation that only wants to RSVP over Facebook? Or participating with a wider collective of groups?

Perhaps my problem is very specific, but I'd like to hear your views if you have similar experiences and what solutions you came up with.

Andrew.