The Holy Spirit did not contract a marriage with the Virgin in the normal sense, of course; nevertheless, she conceived a son by Him and therefore is either guilty of harlotry or entered into some kind of licit, marital relationship with God.Joseph's primary role was to vouch for the chastity of the Virgin since otherwise she would have been stoned for playing the harlot.The problem with the grotesque idea that Mary and Joseph had martial relations is that after the Conception, Mary was united in flesh to God, as Christ says "And they two shall be in one flesh. Therefore now they are not two, but one flesh" (Mark 10:8).Drawing upon this fundamental principal, it was the teaching of Christ and the Apostles that even re-marriage (nevermind intercourse outside of it) was unacceptable: "Whosoever shall put away his wife and marry another, committeth adultery against her. And if the wife shall put away her husband, and be married to another, she committeth adultery" (Mark 10:11-12).The Apostle also preaches the same saying, "Or know you not, that he who is joined to a harlot, is made one body? For they shall be, saith he, two in one flesh... Or know you not, that your members are the temple of the Holy Ghost, who is in you, whom you have from God; and you are not your own?" (1 Cor 6:16 & 19).If you remember, no one was allowed to touch the Ark of the Covenant under the Old Law, and Oza was stricken dead for doing so: "And the Lord was angry with Oza, and struck him, because he had touched the ark; and he died there before the Lord" (1 Para 13:10).In short, it would be gross and mortal sin for Joseph to touch the Virgin maritally because 1) she had already conceived by another person and 2) she had already been consecrated as the living Ark of God.
I don't believe that Mary was in some kind of marital relationship with God, except in the same sense in which marriage is an analogy for the relationship of every devout soul with God. Mary's conception of Jesus by the Holy Spirit was not sexual; therefore I see no reason for her to be wed to the Holy Spirit in a literal sense. The ark is another analogy, and a good one, for Mary, but you are taking it too literally in this argument. I could be wrong and you could be right; I have no certainty about this.