Is it possible to think too much? And where does one draw the line between necessary thinking and overthinking?

Objectivists are people who take ideas seriously; they are intellectually inclined (as far as I can discern) and spend a lot of time "inside the mind." With all this emphasis on rationality, thinking, introspection, analysis, judgement, reading, etc., how does one avoid the frustration or sense of "analysis paralysis" and ultimately depression that ensues from all this deep thinking and focus on ideas. For example, I've heard numerous people in forums or in letters to Dr. Peikoff state that they are depressed about the state of current politics, our culture, etc.

What priniciples or general rules does one use to put the breaks on all the deep thinking and just chill out, "live and let live," and stop one from becoming crazy. Meditation? Get drunk? (Kidding).

On a personal note, I've found that it is necessary for me to literally suppress my thinking and let myself drift into an out of focus state in order to maintain a sense of serenity necessary to get through the day.