The FL left him thinking that he would be happy without her . But honestly who stays happy after being hurt like…
I think you missed out on that part, she did discuss her decision with him about moving out. Her reasoning has more to do with her inner battles and conflict, she does have feeling for him but her abandonment issues is acting up and she does feel guilty for breaking her promise with him years ago.
"Sang Yan's love for Wen Yi Fan is not just genuine love but a safe kind of love"