Dear Newfoundchildhood,
My own personal "aha" moment came when I realized that in my family, people were expected to read minds. If you could not read minds, you had committed a sin. So I went around trying to read other people's minds --- and in the process, tended to assume they were thinking negative thoughts about me or about what I had just said or done. (Because, of course, in the FOO, you would get blasted for your behavior and for not KNOWING better even though KNOWING would have required being a psychic).
I had another "aha" moment when I realized my mother did not know what the heck she thinks about anything. So even if I were psychic, I couldn't read her mind because she would be just as likely to change her mind in mid-thought as anything. She can flip-flop from one opinion to the opposite in the blink of an eye. This was a terrific insight because ... you will never be good enough because there is no set standard. The standard moves around all over the place. And you will always be faulted for not being able to predict where the standard will show up next.
So ... what I did (and still do, I'm not totally over the knee-jerk reaction to try to read other people's minds) ... is always, always ask myself, "So, why do you think he/she thinks that? Why do you think he/she had that reaction to what you said/did? Is it their facial expression? Their body language? Their words? Or is it just because you feel embarrassed and assume that the other person 'must' be thinking bad thoughts about you?" I have found that sometimes when I was berating myself, the other person hadn't even heard what I said or seen what I'd done! They had had NO reaction to what I said/did because they didn't know about it! Yet I was castigating myself because they thought badly of me!
Of course, the next step is to learn to evaluate what I say and do according to my own standards, not whether or not somebody had a bad reaction to it (even if that reaction is real!). That's hard. But the very first step is beginning to recognize when you have no way of knowing WHAT the other person is thinking, and recognize when your prediction that they are critical comes from your past, not from what is happening in the present.
I actually think this process I have described in my post has been the most healing of all of the things I have done.