But husband wife and child are still 3 different person. They don't become one person after the baby is born
If we all agree to what others believe then there is no need to preach. Its important ro debate and discuss. Some of the Christians may not agree to what you believe. For instance i am sure more than 80% of Christians would not believe Jesus as an angel(also u have not given any reference from bible for that)
Why don't you take a poll about who thinks Jesus may or may not be the incarnation of the Angel of the Lord?
The Fact is, the New Testament indicates that Jesus IS the Logos of God, which essentially, in ancient Greek though, more or less equates to a similar idea, and as we see in
the Gospel of John, the Logos of God is ... God.
As I've attempted to explain elsewhere, if we use the analogy of the Light Spectrum, Jesus could in some sense (a very rough, inexact sense, of course since it's just analogy) be of the Light Spectrum, but be discerned by us as but one color of that spectrum. But I do so dislike having to use human analogies to try to explain what is a Mystery of the Faith...
The point is, Christians [more or less] believe that the Logos of God, which is God, transformed Himself and, by the Fiat Power of God, was found within the womb of Mary. No man was involved with Mary; only God's Power was involved with Jesus coming into the world as a man through Mary.
Again, I'm not saying you will believe this; I'm simply stating this so you can better understand. We Christians think that God can transform Himself, or one "frequency level" of Himself, and we Christians also believe that the Logos [the Word], who is with the Father, was placed into this world through Mary. And God did so despite the sinful nature of humanity.
He did so because His love for humanity to care for us and save us is EVERY BIT AS EQUAL AND IMPORTANT as His Holiness is.