Devastated and Wore-out of my preparation..Pls Advice

In my opinion, it is almost always a bad idea to leave your job for GMAT preparation. GMAT is not a goal in itself - it is a means to a goal. Even MBA from top 20 is not a goal. You want something else in life and you think that MBA is a means to achieve it. Also, MBA is one of the means to achieve it. What if in 2 months you feel differently about your current job, say you get offered a role which was what you actually wanted post MBA - whatever. Also GMAT preparation doesn't need you to sit at home. Most people prepare for it while on a full time job; there is no reason you cannot do the same. Quitting your job is an unnecessary risk.

Also, from admissions perspective, explaining a 6 month break is hard. Preparing for GMAT is not a good enough reason - you will need to do some serious convincing that you actually needed to quit your job. Also, GMAT score is just one of the factors considered by adcom. The 6 month break might actually irk them enough to decline admission even if you have a stellar GMAT score.

Instead, try to invest every free minute in your preparation e.g. reading Economist articles while commuting, using GMAT phone apps to practice Quant questions anywhere etc. You have the entire weekend to devote to your prep. Cut down your social life for a few months. Hopefully, your spouse will understand.