I'm not a horror girly, but the plot reminds me of Kazoku Game, one of the first J-dramas I ever watched and a favorite, so I'm definitely giving it a try!
Since I'm not married and don't have much experience in such relationships, I couldn't really empathize with them, and I couldn't help being judgmental of the way they acted and dealt with their problems. But I honestly was rooting for them and wished they could make their marriage/relationship work somehow. It was a reflective and interesting drama. It is a good watch definitely recommend it!
I don't understand why the grandma made Junko fail that exam. Wasn't it a good opportunity to get rid of her since she wants to separate her from Takane?
Also she can't remember her ex's brother?