Hi SLAYGMAT,
It's important to remember that the GMAT is a predictable, standardized Test, so you can take advantage of that 'design' and train to score at a higher level. If you're scoring in a consistent 'range' in the Quant and Verbal sections, then there are clearly some things that you do consistently well, but there are also some mistakes that you also make on a consistent basis.
With a goal as big and meaningful as an MBA, you shouldn't be thinking of giving up - you should focus on what it will take to adapt and improve. You've made some recent steps to improve your situation, but you have to continue working hard and making additional changes to how you approach this Test.
1) What is your goal score?
2) When are you planning to take the GMAT next?
3) When are you planning to apply to Business School?
GMAT assassins aren't born, they're made,
Rich