When I first got back into riding I thought it would be fun to ride with groups and like you I realized I couldn't keep up. I also didn't know at the time how unfriendly most road riders were.(lol)
But then I found the MTB community and the rest is history. I settled into riding fat-bikes on mountain bike trails. Far more fun and safer. Solo rides are preferable to me now.
Love your little ones, I too am a proud owner of multiple rescues.
I hope you find what you're looking for in a club.