The scriptwriter started with a good premise, the idea of interwoven rifts in several marriages, and asks some deep and revealing questions about love and marriage. However the reasons for relationship breakdowns in this story are ultimately trivial things, or reduced to unbelievably flawed characters.
We don't discover until most of the way through the season, the perfect housewife that's secretly cruel to her mother for no justifiable reason; the devoted stepmother that slowly kills the husband off 40yrs so she can pursue her adopted stepson; the aloof wife who is unbelievably popular despite looking like Walmart trash-diving racoon and having zero real musical skill, somehow treats her amazing husband with nothing but venom; the A-list singer who has flocks of adoring fans, but decides to breakup an ideal family to get back at the ex-boyfriend who mistreated her, only to go back to the ex afterwards. Meanwhile three of the devoted housewives flirt daily with their radio station boss, even though he's a middle-aged playboy who dresses like kkangpae.
The second season has much of the same story slowly evolving, and we see the families and then secondary relationships begin to unravel.

Outstanding performance from Jeon Hye Won (playing Park Hyang Gi) who is supposedly a 20 yo daughter of divorcing parents, but in most scenes she's would have been far more appropriate if cast as one of the wives / experienced mistresses -- her dialogue was several times longer than either of her parents' characters and far more aggressive and angry than almost any other character, which is illogical for a young daughters' role.

A Golden Turd goes to Lee Hyo Choon for her performance as Mo Seo Hyang -- with almost zero dialogue, facial or bodily movement throughout the series, she managed to reprise Bernie from Weekend at Bernie's. Setting a record low bar for substandard acting in KDrama.