Is this because Holy Tradition teaches that Mary is the spouse of the Holy Spirit?
It is, as far as titles go, useaful to understand Mary. However, observing your excitement ofver this discovery, let me make a broader comment. As a rule, Protestantism, born out of cheap slogans, also thinks in slogans (a slogan is what Luther nailed to the rear bumper of his folk wagon). You go: Faith Alone! I've Been Saved! No King But Christ! and think that is all there is to Christian religion. So you think that Catholicism -- religion matured in the Middle Ages when people had time to think and knew how to do it,-- operates like that, too.
Catholicism treats simple matters simply and complex matters complexly. Just because you picked up some expression of piety does not mean you grasped the theology. Mary is a human being who had a grasp of divine nature like no one else. In treatment of her, especially, Protestant crudity of thought looks particularly squalid.