There is a general misconception that God is the Father and that we are something far less than sons and daughters to Him, but this is not actually true. We are much more than what we often think that we are, for we are, in truth, co-creators with God himself. This means, that just as God has no beginning and thereby no ending, so we too have always existed in the Word of God and will always exist as co-creators to the Master Creator himself. The confusion as to our immortality rests in the wrongful assumption that the physical body is our essence, it is not, as it is merely the recipient of our mind, our spirit, and our soul. Further to this confusion, is our own unworthiness in sin as well as in our actions, which convicts us within our very essence that we are unworthy to completely re-unite with God, until we have shaken off or worked out our own imperfections so as to be perfect in He who is perfection Himself.
Another question might too be raised as to why would any soul wish to ever leave our Lord in the first place, but here though is the lesson of the prodigal son which applies to all who reside here on earth, that those that wish to have what is rightfully theirs as an inheritance will have this given to them, as God will not stand in the way of any soul exercising its own free will, and when that soul finds out, as all must, thattheir way is not the way, he will return, humbler, but at the same time, welcomed in open arms by the Lord who turns none away, no matter how far the journey, and no matter how distant the country.
Jeremiah 1:5 reads: "Before I formed thee in the belly I knew thee," which signifies that before our birth onto this earth plane, that we were already in existence, so subsequently no new souls are created, they have always been, and they will always be, as you cannot create immortality out of mortality. God is omnipresent, He is everywhere, and we are created in His image, not as pathetic imitations or little puppets, but as one in the Father--no less and no greater than He. Any perceived separation from our Father which art in Heaven is our own misreading of what is available for each and every one of us.
It too might be helpful to picture yourself as a little child with a new toy, a fascinating toy that can do just about everything that you could possibly imagine or that you could possibly put your mind to, while no doubt, there would be great things of beauty you might well conceive of, so too, there might be great things of horror, such as the unleashing of your very own Pandora's box. Yet, through it all, good or bad, in the end, all will return to how it was in the beginning, as nothing mortal can ever overcome anything of immortality, no matter how dire or pleasant it may be. Remember from John 1: 5 that; "The light shines in the darkness, and the darkness has not overcome it." We that are one with God, are that light.