Congrats on the weight loss. I too am a lone rider, a rebel, Dottie. You don't want any part of me. (misquoted Pee Wee Herman reference). I am encouraged by this post as I have never been on a group ride, but am feeling the urge (hence my posts about the agony of choosing a proper road bike).
Since committing to cold weather riding this year, the strength gain has been quite noticeable, but the curiosity of what a group would do to my performance is growing.