Sounds pretty legalistic to me. So, she was Josephs wife in name only with no intention of ever consummating the marriage? That's probably not what Joseph had in mind when he first proposed. This sounds like deception on somebody's part. But Blessed Mary was not that kind of girl. Happily Jesus had some half brothers later. I think James was one of them. So it ended well after all.
Interestingly, although the Muslims affirm that Mary became pregnant while a virgin, they deny that God is the Father of Jesus Christ --- they deny the conception of Jesus in the womb of Mary by the paternity-power of the Holy Spirit. They say, rather, that God (Allah) created Christ in the womb of the Virgin Mary, and as a result Jesus really had no (begetting) father AND no (genetic) mother: he was simply created parentless, as was Adam, and placed in the womb of Mary as if in an incubator.
Part of the Muslims' reasoning is that they say that Almighty God would not take somebody's wife in an act of --- they would call it--- divine adultery.
But they are wrong, because
It's logically impossible to make generalizations from single instances, so I think all of these things apply to this situation alone, and none of it is directly comparable to any other person's marriage situation before or afterwards.
Jesus had no full brothers or sisters. If he had half-brothers or sisters, they were the widower Joseph's children that he had in a previous marriage. Or the "brothers" mentioned in the Gospel were other close male kin, cousins and so forth. The word "brothers" in a Biblical context --- as we can see in many Scriptural texts --- does not necessarily mean other children of one's father and mother.
Cousin...
COUSIN!
--Rome