Existentialism and Common senses

Doubtless, we are living in the age of existentialism. But a relevant significant point to existentialism is: "since existentialism is depend on individuals, there could not be a common rule for all individuals to do and follow and so every individual has to follow h/is own way of thought. So nothing to share with others and nothing to ask of others, because of difference in very fundamental part of human existence.
I believe that, we need to revalue it, in order to make it more depend on society, more depend on human community; and more depend on common rules. 

But no doubt, existentialism is prior to common senses.