I don't think Doyun is totally innocent because he was neglecting his relationship but coming from someone who dated someone who was cheated on people can really be hurt forever having been cheated on. Sure Wonhae didn't really cheat but he made Doyun think he was. I have an ex who was cheated on by his previous girlfriend because of that he was so insecure and jealous. Because of what someone else did to him in the past it ruined our relationship because I literally couldn't do anything with out being scrutinized.
Making your partner thinking you have cheated many times, is the worst kind of person. I know that feeling insecure because of what we have experience especially got cheated by your own partner. Causing depressed and lost trust toward other.
I don't think Doyun is totally innocent because he was neglecting his relationship but coming from someone who dated someone who was cheated on people can really be hurt forever having been cheated on. Sure Wonhae didn't really cheat but he made Doyun think he was. I have an ex who was cheated on by his previous girlfriend because of that he was so insecure and jealous. Because of what someone else did to him in the past it ruined our relationship because I literally couldn't do anything with out being scrutinized.