I dont have the answer you want, but this might help.
another of my fav lines : Study your errors and explain the solutions to yourself.
Keep a binder and start updating it with ALL problems you get wrong. Write down the mistake and explain it to yourself what is the correct way. Even for the problems you do get right, make sure you understand the correct solution. I am sure you will improve.
Allow me to post a comment to our new friends here. its not necessarily related to your problem.
Summary of my rambling below :- Solving problems by using Process of Elimination (POE) is absolutely NOT cool for learning , but cool when taking practise tests. i will try to explain
Just a note to our new friends here, while i remember it : In your prep, especially for the verbal section, Process of Elimination is the WORST way to learn concepts on the GMAT. POE cripples your thought process. POE should be your last option when you prep. its a temptation you must resist in your prep. otherwise, all you would be doing is getting a problem right. you wouldnt learn anything significant.
POE is great for tough problems on practise tests, I dont mind if you have to use POE on the practise tests, but NEVER use POE as a learning tool.
I hope i made the distinction clear.
Praetorian