In the Church, Christ is the bridegroom and the Church the bride. It's a sort of symbolically sexual thing, I'm having trouble putting it into words. Jesus emptied himself for us (us being the church), so it explains why there can be no women priests, it's just physically impossible for a woman father a child. So anyway matriarchal priestess religions would represent a subversion of God's creation.
I'm really not explaining this well, derp.