A neurosis is a secret that you don't know you are keeping.
Society expects man to be a passive social animal who believes like the People of the Field in "Jurgen" that "to do what you always have done" and "what is expected of you" are the twin rules of life. This, of course, is not true. The wanton crucifixion of impulses, the unnecessary blocking and frustration of the drives and urges, are an evil that reflects itself in sophistication, ennui and boredom, dissatisfaction, melancholy, fatigue, anxiety and neurosis.
Neurosis is the inability to tolerate ambiguity.
I have frequently seen people become neurotic when they content themselves with inadequate or wrong answers to the questions of life. They seek position, marriage, reputation, outward success of money, and remain unhappy and neurotic even when they have attained what they were seeking. Such people are usually confined within too narrow a spiritual horizon. Their life has not sufficient content, sufficient meaning. If they are enabled to develop into more spacious personalities, the neurosis generally disappears.