The Wonders of Eternity

What is the nature of of the soul of mankind?  What is this mysterious union of flesh and spirit that gives us our mortal life?   Are we nothing more than complex electro-chemical organisms or is our body of divine design housing temporarily an eternal spirit child of God? Think of the billions and billions of people that have lived on the earth, that now live and will yet be born. Where did our spirit come from?  Is our existence here for the purpose of taking a step towards an eternal and divine destiny to become like our Eternal Father or are we mere creatures placed on earth because some mysterious presence in the universe became tired of being alone up to a point in eternity about 6000 years ago? What are the existing doctrines of mainstream Christian theology and why is Mormon theology on the nature of our spirit so unique.  This is my own opinion as to how they are taught in the religious communities based on study of the various theologies put fo...