It's just about Hollywood trying to make cheating on your partner a good thing!
That's what I've seen and learned, Hae sung the male lead is portraited as a huge simp based on something about a mystical theory about love. Travels thousands of miles just to see a childhood crush who got married to an American guy named Arthur!
And Arthur even though he's very hurt by seeing his wife still having feelings for him(hae sung),still allows his wife to have meet ups with hae sung. And also to make it worse She brings hae sung to Arthur's house. The audacity to do this much,to hurt your husband like that, and to top it off she cries after hae sung leaves and Arthur, the husband consoles her for crying after another man!
(Hollywood knows how much influence it has on its audience and the problem is the people not realizing it)
Tryna make it really subtle huh, but guess what, it having a partner having feelings for someone else is just not gonna work out.
Overall nice movie if you like drama and painfully movies!