Cuckinny,
Thanks for posting your (and your wife's, I gather) interesting observation:
which I've neither heard nor read of anywhere else.
When you say your wife "smells like her lover for the rest of the day," do you mean she smells like his semen? Or, do you mean she smells like his sweat, which would be different? Your answer to this question may provide a clue re. the source of the smell.
If this statement is from your point of view, that may be because you're accustomed to your own smell so you don't notice it. If this statement is from both your and your wife's points of view, one would think she would notice it because your smell is different from hers... and because women, generally speaking, have a significantly better sense of smell than men.
—Custer