Call it a natural process, I think everyone goes through it at sometime, to some degree or another. Have done some national events, and as pointed out, you see all kinds of riders. Have done Rolling Thunder in D.C. for one, and although its one of the most moving rides I ever did, the stress of riding with a bunch of strangers takes a toll on you. So our group of friends that I trust and feel comfortable with has shrank to just a couple of riders that seem to enjoy the same type of riding. Most everyone on this thread has said or done the same thing.
Yep....when two up with my wife, who loves to ride as a passenger, the though enters my mind about her safety. Funny when riding by myself, I never really think about it.
As long as I can swing my leg over the seat, and that deep growl when I push the start button brings a smile to my face, I'll still do it. If I become a hazard to those around me, my friends are close enough to me to tell me the truth. I just hope I am man enough to accept it.