David,
Ultimately the choice to continue will be yours and yours alone but bear this in mind:
1) Decide how you are likely to feel about this in five years time. If you think you will regret not continuing then heed the advice on this forum and find a way round your problem. If you decide your feelings toward aviation will be the same as when you wanted to give up, then perhaps you should kick it into touch.
2) Generally instructors believe themselves to be better than they are because they spend their life flying with novices. The really good ones do not change their style from student to student because they don't have to, they are universally good (there is one particular QFI at my workplace who personifys this, he is the same with every student he trains and always gets excellent results). Something I strive to attain but in reality know is beyond me. Still, no harm in trying.
3) Don't be scared to vent steam, I've had some right bollockings off students and every one of them was justified. What really annoys me is when I screw up (of course I do, just like everyone else) and the student has complained behind my back. You may be surprised that sometimes confrontation works!
4) No-one knows it all, if you think your instructor has given you duff gen then question him. There are NO stupid questions in aviation, only smug answers.
David, feel free to heed or ignore any or all of this advice. However, as an instructor I would be grateful for more information on your personal experience. If I can avoid inflicting on others the kind of experience you have gone through then something positive will have come out of it. Please PM if you have the time.
Regards and good luck with whatever you decide.
Jim Nicholas