It appears that you contradict yourself: "There are some who will say that the word betrothed meant that they were merely engaged, but scripture shows differently ..." Mary was already betrothed to Joseph when Jesus was conceived in her womb. When the Angel visited Mary to tell her what was going to happen, she was already betrothed to Joseph, she was already in a marriage contract with Joseph. Your comment shows you understand that so long as she was still betrothed to Joseph, she was not free to be the wife of another unless Joseph had divorced her. Whioch divorce The Angel told Joseph not to do. Somehow you have inverted the first betrothal to read in your argument as God was first betrother. THAT IS NOIT ACCURATE based upon your own quoted passages.
Further, you make a huge assumption not supported by what you've offered: "Her response only makes sense if she had no intention of having a conjugal relation with the man she was already betrothed to." That is an aside, not a portion of the argument you have posed. It is an assumption not supported by any data in evidence. It makes Mary to be duplicitous, continuing in a betrothal to Joseph that she has no intention of honoring after she gives birth. I don't have that image of the Blessed Mary, the Mother of Jesus. That is an implied dishonesty not warranted by the data presented.
Please re-read what I wrote, Mary was in a “spiritual” relationship with the Holy s Spirit. It was addressed in the article.