Affects of Criticism on Self-Esteem and Self-Confidence.

At what amount (in respects of no. of people, no. of times and severity) of criticism from the others, one normally starts to have self-doubt and his/her self-confidence is broken? At what amount, IDEALLY should that be happening? Infinity?

I used to be unable to handle any type of criticism. Everything anybody said began to feel like criticism after awhile.
It was partly due to a large ego and little self-esteem. It was also due to being too close to mom and having severe depression when I lived at their house under their roof.
I began to feel better about myself and was able to handle criticism better after quitting drinking and receiving treatment for depression and anxiety. I was alcoholic and felt bad about myself for that.
Sometimes a disagreement will flash me back into the past feelings, but I don't stay with that feeling for very long. It used to eat me up and I was constantly angry and depressed about any kind of disapproval at work or at home.
Criticism can be used to control you in a relationship. It can be used to keep you from moving forward with self-improvement.
The amount that criticism affects you can vary. There is no set amount. If you feel that it is intolerable, do a personal inventory of yourself and go with it to a professional for an evaluation.
Best of luck to you.

I think it really affects people differently. I am very sensitive to begin with. Add critical criticism and even constructive type of criticism can be difficult to take at times. With the help of therapy and feeling like I am a good person, and that at my own pace, I can be able to handle any type of criticism, I can move forward in a positive way. It helps to have others who really know you even your therapist give you uplifting words. You tend to believe it and internalize all the good from that.

I come from a background of receiving only or mostly negative remarks about anything I said and did. I got constantly criticized. For years as a teen. Mentally I am strong but sometimes I feel so inadequate and have a hard time believing I am good enough. I had 5 of my teen years like this. It really affected me.