From your source: This is the story of Our Lady of Guadalupe as recorded by Luis Lasso de la Vega in 1649, a translation from the Nahuatl indian dialect. This was written 118 years after the event.
Though your source is good, it is the third and later telling of the story of Guadalupe. The following is taken from the first and oldest account, written about 1540, nine years after the events occurred.
The following account of the five apparitions in three days is based on the oldest written record of the miracle of Our Lady of Guadalupe, the Nican Mopohua, written in Nahuatl about 1540 by Don Antonio Valeriano, one of the first Aztec Indians educated by the Franciscans at the Bishop's Colegio de la Santa Cruz.
"I am the Virgin Mary, Mother of the one true God, of Him who gives life. He is Lord and Creator of heaven and of earth.
I desire that there be built a temple at this place where I want to manifest Him, make him known, give Him to all people through my love, my compassion, my help, and my protection.
I truly am your merciful Mother, your Mother and the Mother of all who dwell in this land, and of all mankind, of all those who love me, of those who cry to me, and of those who seek and place their trust in me. Here I shall listen to their weeping and their sorrows. I shall take them all to my heart, and I shall cure their many sufferings, afflictions, and sorrows.
So run now to Tenochtitlan and tell the Lord Bishop all that you have seen and heard."
Notice the bolded section. It is not recounted in the later source. Most importantly, notice that Our Lady does not request that a temple be built in her honor but that she desires to "manifest Him, make him known, give Him to all people". Also take note that she does so "through my love, my compassion, my help, and my protection".
The story of Guadalupe is much more than Mary's appearance to Juan Diego and the events that followed. Fifteen hundred years earlier, Mary said yes to the angel Gabriel and 9 months later brought forth her first-born son. She did this through her love, compassion, help and protection to manifest Him, make Him known and give Him to all the people. In 1531, she brought Christmas to the New World again desiring to manifest Him, make Him known, give Him to all people through her love, compassion, help, and protection. Thus she brought glory to God by bringing Him to the New World.
To Jesus through Mary.
"A great sign appeared in the sky, a woman clothed with the sun, with the moon at her feet, and on her head a crown of twelve stars."
The Image on the Tilma
The imprint of Mary on the tilma is striking, and the symbolism was primarily directed to Juan Diego and the Aztecs. The description that follows is that related by Father Elizondo,7 who references earlier writings. Mary appears as a beautiful young Indian maiden with a look of love, compassion, and humility, her hands folded in prayer. Her pale red dress is that of an Aztec princess. Her blue mantle symbolized the royalty of the gods, and the blue color symbolized life and unity. The stars on the mantle signified the beginning of a new civilization. Mary stands in front of and hides the sun, but the rays of the sun still appear around her, signifying she is greater than the sun god, the greatest of the native divinities, but the rays of the sun still bring light. Twelve rays of the sun surround her face and head. She stands on the moon, supported by an angel with wings like an eagle: to the Aztec, this indicated her superiority to the moon god, the god of night, and her divine, regal nature.
Most important are the two crosses and the black maternity band that were present in the image. Mary wore a black maternity band, signifying she was with child. At the center of the picture is found an Indian cross, the center of the cosmic order to the Indian. This symbol indicated that the baby Mary carried within her, Jesus Christ, the Word made Flesh, is the new center of the universe. On the brooch around her neck was a black Christian cross, indicating she is both a bearer and follower of Christ, the Son of God, our Savior, who died on the Cross to save mankind.
In summary, the image signified Mary bringing her Son Christ to the New World through one of their own!