Hye-won (played by Jang Hee-jin) is Do-woo's wife and Annie's mother. In the aftermath of what happened to Annie, Hye-won's behavior is...odd. She doesn't really act like a grieving mother. Everyone grieves in a different way, and this is why Do-woo doesn't push hard on this point, but the scenes we see which Do-woo does not clearly imply that Hye-won's actions are suspicious. Soo-ah's husband Jin-seok (played by Sin Seong-rok) similarly does not see eye-to-eye with his loved one on what to do, although their situation is admittedly far less extreme.
It can't really be ovestated just how awful Do-woo's situation at home his. Do-woo's mother Eun-hee (played by Ye Soo-jeong) is public yet stingy with grief, and live-in apprentice Min-seok (played by Son Jong-hak) isn't even really family and can only be bothered to give the minimum effort when it comes to caring. That Do-woo did not interact with these people much in the first episode is of little surprise- Annie was the light of his life. And now she's gone.
This is the backdrop from which Do-woo comes to rely on Soo-ah to help express his belief. He just doesn't have any other options right now. This is heartbreakingly sad and Soo-ah knows it, but for precisely this reason she can't bear to let him down. Soo-ah is a very empathetic woman, and has realized correctly that Hyo-eun is hurting badly after the death of her best friend.
But Jin-seok isn't much help to her either. I find Jin-seok to be an interesting character, because while his manner is certainly brusque and borderline cruel, his actions in regards to Hyo-eun are clearly in the tradition of tough love. His ideas about emotional recovery in the face of trauma aren't objectively wrong. But they are probably subjectively wrong considering the kind of girl Hyo-eun is. Unfortunately Jin-seok is not used to negotiation when it comes to proper parenting tactics.
The emotional distance between the various characters in "Road to the Airport" is the drama's consistently most tragic element. Technology continues to be a powerful metaphor for how far away everyone is from each other- Soo-ah and Do-woo only ever seem to run into each other by accident, and barely know each other, yet to date they are by far the best communicators, and it's hard to dislike them for the stirring of an emotional affair. Do-woo is struggling to move on, and right now, more than anything, he just needs someone to listen and understand.
Source:HanCinema