Will I do this again? I don't know. I really am intrigued by the social aspect of cycling, but at the same time if I cannot match most groups' speeds, what's the point?
I'm a guy that can keep up with the pack, and my experience has been that group rides are only social before and after they start. A "social" ride has always seemed to me to be an oxymoron because as soon as the ride starts it's basically a competition to see who finishes first. Consequently, I rarely go on these types of rides because I'd rather enjoy the company of fellow cyclists.
Try looking for a "no drop" ride, where the front of the group paces itself according to those in the rear.
When I read your post I was very impressed with your effort. If the other guys didn't want to talk to you during the ride screw 'em. It's their loss.