Re: verbal abuse from a teacher
Getting shouted at or berated because you did something stupid or irresponsible is very different from being shouted out over petty things for the sake of character building. Different people react in different ways, and need to be treated accordingly. Some people may benefit from a harsh word here or there in extreme situations to get the point across, but it is a very tricky line line to tread.
I'd suggest that you need to be clear about the distinction between what is a "justified" telling off and bullying nonsense. Only you know whether the times when you have been scolded are justified. By the tone of you letter it doesn't sound that in every case that you feel it was justified.
Numerous people are warning you that any attempt on his behalf to coerce you into hiding his treatment of you raises serious alarm bells.
If you want to continue to train under this instructor I would suggest that you set clear boundaries about what is acceptable behaviour you are prepared to tolerate in the training process. If you are taking it personally and it is affecting you in negative way then it is not really having the desired effect anyway.