Re: Husbands, Wives, Mil(s), Dil’s etc. The Married family dynamics:
Excellent response. Loved it. Bravo! 
You moved the discussion towards another angle.
No. They were not appointed as husband and wife. **No such thing even close to, them being appointed as husband and wife is valid or proven.
**
**They were given the job of being mother and father to procreate human race. OR they assumed this role out of God’s will.
Actually Shaitan made them like each other and they were then sent to earth since they disobeyed.
**
Moreover:
As much as it would bring some sort of enlightenment to those who may not have thought about it, that even siblings in initial stage were allowed to have intimate relation and become father(s) and mother(s) so the human race could flourish.
**There was no concept of being husband and wife at that stage. **
**Being father and being mother to continue human race is what has been the reason why you and I exist in this world.
**
Later this concept was changed when it was not needed and this is my theory that when genetic code became too close to each of ‘distant cousins’ to cause potential harm, the new orders came, to abolish siblings of same parents become 'pro-creators".
Idea was not of husband and wife by itself, the idea was to flourish human race by making them mother and father.
Adam and Eve (Amma Hawwa) are not remembered as husband and wives since there was no concept of being married.
They are still remembered as father and mother.
(Anything above is not applicable to evolution theorists)