I often struggle with BIG groups because the peer pressure gets to me and then I (repeat I) begin to behave like a mad idiot. Going too fast, knee down etc.
However, after my children arrived, I have become a more responsible rider (aka boring and old).
I'd rather be "old and grumpy" and alive, than cool and dead in a body bag.
Choose your riding pals carefully and choose your friends wisely.
Not everyone who knows you is called a friend.