Thanks for adding that in there. I touch on that from time to time as well, although not in as a great a detail as you did here. Sexually exclusivity only become marginally more required for men during the Victorian era, but even then, "boys will be boys" was still somewhat expected, particularly for the rich.
"But even with patriarchy, it was really only women who were expected to stay sexually monogamous. Infidelity for men never carried the stigma or the sanctions that it did for women until the mid-Victorian age. Prior to this time, prostitution was seen as just a fact of life, a necessary thing in keeping with the early Victorian jingle, ‘Hogamus higamus, men are polygamous/Higamus hogamus, women are monogamous’, with the added detail that ‘the majority of women (happily for them) are not very much troubled by sexual feeling of any kind. What men are habitually, women are only exceptionally.’ Source
But by the 1870s and 1880s men were admonished to transcend their “animal instincts” and “considerate” husbands were the ones who did not make too many sexual demands on their wives. Private male homosexual acts were not explicitly or severely legislated against until 1885, when gay sex even behind closed doors was made a criminal offense for the first time and moral panic over prostitution became a topic of increasing focus. The hogamus higamus days were over and both men and women were expected to be “sexually continent” outside of marriage."