I am not sure how to respond. I do know that it ain't right and he is wrong for abusing you. You probably have to decide if you want to stay and take it or move on. If you really want to stay then I would take him aside and ask what is up. The truth of the matter is you are paying himn for instruction not abuse. Basically he works for you and you don't have to take that. Of course don't presend it that way. Have you tried to ask the other students why he is the way he is? Is it just with you?
It is a hard situation you are in but stay strong and decide if you want to continute with this guy or move on.
Again, no instructor should belittle a student in that manner.
90 percent of good abs is your nutrition