We believe that God the Father is the father of all our spiritual bodies, that’s true. (We’ve never had an official doctrine to my knowledge about a “mother in heaven,” but it makes sense.) But we also believe that before we had spiritual bodies, we will existed in some form. Sometimes it is referred to as intelligences, and that intelligences are co-eternal with God.
But that's not in Scripture, yet you take that as fact.
The closest thing that I know of in Scripture concerns God's knowledge and plan for those whom He would later create, not that they previously existed until creation but in His own mind:
"Now the word of the Lord came to me saying, 'Before I formed you in the womb I knew you, and before you were born I consecrated you; I haw appointed you a prophet to the nations." (Jeremiah 1:5)
"For whom He foreknew He also predestined to become conformed to the image of His Son, that He might be the first-horn among many brethren." (Romans 8:29).