Uhm, they needed to marry and produce an heir?!?? The literal best choice for her was the husband, whom she too has feelings for. Would u want her to get with someone who has the status but is a new complete stranger to her??!?! Did u not read the manhwa or what. Also, the problem wasn't him, its their parents that pushes the heir idea. All he did is ensure his wife get best treatment despite the unfairness of the moment. And I'm pretty sure if the husband is cruel, he wouldve fired Seok and not let him linger around. Bruh u read with ur eyes closed is it

The husband and the man were real ones, both of them are honourable and do what it takes to make the woman they love happy regardless of the situation. Love how none of the men shame the woman despite it being an unfair moment. The woman is a good woman for not letting it cloud her judgement and duties of a wife.