Hey...
Well, I can understand your frustration especially after all this intensive study.
I took GMAT before one month and scored 540 though I went through two month study, covered Kaplan, Princton and other books. I was scoring between 530-570 in Kaplan’s tests and around that with the Preps.
I am now going for another shot after one week. Hopefully I will pass 600.
I see that you are almost facing the same problem with Verbal Section. My advice for you is to try to focus more while studying. In other words, it doesn't matter how many books or exercises you cover as much as the level of understanding of the exercise itself.
Don't give it up. I guess long months of study can do an adverse effect. So try to put a one month calendar and sum up all what you went through previously.
Best Luck