How am I supposed to know what I don't know?

More music lesson ranting

Last week he was telling me how far I've come,how he so proud of me, and such - and this week he's telling me that I have hit a plateau and that I need to focus on what I don't know. Because "Do you how how much you don't know?"
Um, a few points here.

A) I am taking these damnable lessons because I want to learn what I don't know.

B) If I knew what I don't know I'd know it already.

C) I have been playing two years come the 20th of this month and you have been playing for about 40 - you damn well better know more than me. If not either I am a prodigy or there is something seriously wrong.

D) if you tell me that if you have me play it over and over and " your fingers now how to fix it" then I ain't as bad as you make me feel.
and
E)I ain't so stupid that I need baby books. "Kid Fiddle" and "I can read music" are aimed at very young kids...even more so than the books I like. Stop trying to treat me like I am 4 years old.

I don't even want to practice anymore, I've *always* loved practicing, even through Viki's worst, even when I was leaving in tears every week. I don't even want to see the thing any more.
How do I do I recapture my love of it...and more importantly How am I supposed to know what I don't know?

Sigh.