As DuffyDuck said, it makes a big difference if you're in control of the aircraft or not.
If you're flying, your mind stays focused at what you're doing at the time and you also expect the onset of the G's, but if you aren't, it "slides" to the "what if i get dizzy now
" thoughts and the G's get you unprepared.
Its the same with drivers and passengers of road vehicles, the driver never gets dizzy (unless he has a health problem).
So, explain to your instructor that you want him to try to instruct verbally and demonstrate as less as possible, so that you fly as much as possible.
