you don't love him

it's been a year but your marriage to Sunghoon is empty because you are both busy as doctors and rarely communicate, he is a specialist surgeon and you are a novice surgeon which makes you bored with your marriage

One day there was an accidents that made you have to intervene to operate on someone for the first time and on that day you met your ex. Since you met your ex, you often take the morning shift and spend the night with your ex instead of going home with Sunghoon

in the afternoon, when you come out of the hospital to go to your friend's apartment (it's just an excuse because you're actually going to your ex's place) he takes your hand and speaks with a stoic face

"You're going to your friend's apartment again? Listen, you're my wife so you don't have to go to your friend's house every day" he said in a flat tone

"It's up to me, you always come home at midnight, as long as you know I'm lonely at home alone" you said defensively