Meaning of "Whose husband only knows her not a whore"

Question

From Byron's Don Juan:

Oh beautiful! and rare as beautiful
But theirs was love in which the mind delights
To lose itself when the old world grows dull,
And we are sick of its hack sounds and sights,
Intrigues, adventures of the common school,
Its petty passions, marriages, and flights,
Where Hymen's torch but brands one strumpet more,
Whose husband only knows her not a wh-re.

Just to make sure: is the meaning here "only her husband thinks that she is not a whore, but all the rest know that she is"?

Answer 1

I'm tempted to say this belongs on ELU, but ...

Almost. It's not clear what the husband thinks, but I'd say it's implied that he's blissfully ignorant.

A more prosaic rendering would be “it's only [her] husband who doesn't know that she is a wh-re”.