Excuse me my friends. I told my older sister about a fanfic I read about a long time ago and now I want her to read it. Please help me find it.

The main person is Chanyeol and the main person has a sickness where she sees things others can't and she sees Chanyeol as her boyfriend when he actually isn't and is a famous star. The doctors say that if she doesn't get treatment then she'll be stuck in her own world. The treatment is for Chanyeol, the famous star, to be her real boyfriend so therefore, the mother sends him a letter and he agrees with the help of Kris and Lee Soo Man. Throughout the story Chanyeol and the main person actually fall in love and become a real couple (I think). In the end she dies from stage 4 cancer and leaves Chanyeol with a note she's written to every Exo memeber, including him.

It'll be a big help if you guys find it. Thank you!