Though I took a lot more words in saying it because of expressing what happened in greater detail (in my lengthy post on page 8 of this thread), what you said essentially is the main problem I've had with the storyline from the start of the game: Here is a loving and committed husband and wife who have not had sex as a couple in four months on the first night of their vacation, and the wife seems far more excited about doing things with men other than her husband.
Even on the paths where the husband prevents things from going further, she's putting her hands on the bare chest of another man while dancing; she's getting drunk to the point of letting her top slip off her breasts; and if the MC doesn't closely regulate her actions as she dances, she walks aways without telling him where she's going ("to clear her head"), only to be found sitting at a bar with another guy who she fails to tell she is married and allows to get handsy with her and buy her a drink in exchange for being sent a dick pic.
So I can somewhat understand the "honey I thought that's what you wanted based on your porn viewing history" explanation and perhaps her being a bit too intoxicated, but neither reason seems adequate in explaining how quickly and easily motivated she becomes in acting like an unabashed flirt, ultra size queen, and avid cumslut. The idea that there's some sort of corrupting influence on the island itself at work is the only explanation that potentially could make sense to me, though on most paths thus far it seems that the wife is more susceptible.
