I get the impression that many psych professionals don’t grasp the level insight that people with mental illness can achieve over the years. I think many people with mental illness eventually get to a point where they know their own red flags. Knowing your own red flags, and then spotting those red flags, can also cause fear in and of itself, as well.
My relationship with my mother is one area that goes red flag central for me most of the time. When I am doing fairly okay, it is easy for me to just accept the way she is, flaws and PD dysfunctions and all, and just pay it no mind, roll it off my shoulders. On the other end of the spectrum, when I am doing very poorly, my mother seems supernaturally evil to me and I both despise and fear her greatly. So it’s like a gauge of how well I am coping with stress in general, and how my mind is reacting to it. It’s not that my mother won’t be a source of stress at times, but rather the way my brain interprets and responds to it.
This can also spill over (and often will, at some point) into my fear of even random strangers, like the gas station clerk where I buy my cigarettes, as an example. Or the transition between, “The neighbor guy is going out to his garage for some reason that is his own business,” to “The neighbor guy is trying to watch me through the windows, and he knew I would be by french doors at just this time.”
And so on and so forth. So I would agree that fear of people can be a sign for some people, since it is for me. Not that some people are not stressful or even potentially dangerous, but it’s like that transition between basic self-protective common sense, and an overwhelming feeling of being hunted.