GMAT Strategy

Hi,
I had started preparing for GMAT 4 months ago with immense dedication and a passion to crack it. I had an initial target of 750 and mind, and hell yeah! I still want to get there. I was regularly giving 3-4 hrs on my prep most of the days. I was preparing seriously despite going through a terrible brekup and a hell lot of work pressure!!
I had also given tests weekly to track my progress and worked on my mistakes. I have solved most of the questions thoroughly and learned the concepts. Following are the materials which I have used

OG 12(Math and Verbal)..Redid the questions that I got wrong twice
OG verbal review second edition
Manhattan Sentence Correction Guide
Kaplan 2010 Premier Edition
PowerScore CR Bible
Manhattan Word Problems and Manhattan Inequalities guides
Nova Math

When I say I have used those materials, I have made notes from them and also reviewed my notes periodically.Now Zeroing down to the problem.

My performance on the practice tests has been completely inconsistent. If I score well on quant I mess up with the verbal and vice versa. If I perform well on the verbal section on one practice test I mess up the verbal part on the next. This will of course be evident from my scores as you see

Date Test Quant Verbal Score
7-Jul Kaplan GMAT 36 34 560
5-Sep Knewton 43 37 640
29-Aug Kaplan GMAT 44 34 620
19-Sep Kaplan GMAT 40 32 610
26-Sep Kaplan GMAT 42 41 660
3-Oct Kaplan GMAT 37 24 550
10-Oct GMATPrep 50 31 670
17-Oct GMATPrep 49 27 640

The problem I faced on the last two practice tests (the GMAT Prep Ones) was that nerves took over me during the exam. I was immensely tensed in the verbal part.
It started like a chain reaction. I have some difficulty in comprehending CR and RC when I read through it the first time, So around the 6-7th question when I get the second CR and the first RC I spend a bit of extra time on it, and still if I don't understand/solve it I end up getting
Tensed. This Carries on like a Chain reaction, the tension keeps on increasing and I get most of the questions Wong (got 5 wrong in the first 10),4thQ (SC), 6thQ(SC), 8thQ(CR), 9thQ(RC), 10thQ(RC).This morale continues throughout the test and I end up getting 14-15 questions wrong .Of course I do understand that it is not about the number and that the test is adaptive. My morale is low and I feel like giving up and postponing the exam despite standing all the odds till now

I have 2 weeks or go for my exam and have taken an off from the office for two weeks, and was already not going to work from the last two weeks. In the coming two weeks I can dedicate 12 hrs per day. I can do anything to crack it, I Just want to get to 750.
Despite not even touching a 700 on the practice tests:(

I plane to redo the questions in OG 12, Verbal Review 2nd edition while revising Manhattan Sc guide. I also plan to give 4 more tests until my main test.

I need some serious advice and in immense need of some expert help. I would be grateful if someone can help me, by putting me on to the right path and help me achieve what I am desperate about.