This time I have cut off myself from everything else. NO TV, NO FRIENDS.....Just Work, come home and study.
I sometime do my prep at a cafe by the park, sipping a cuppa and once in a while watching people go by. I also spent time in social activities and especially with my wife and daughter. I tried to keep as healthy lifestyle as I could during my prep, and I found all these helpful.
If other parts of your life (e.g. relationships, work, spiritual, etc) are affected, your GMAT prep is also likely to be affected.
Anyway, all the best!