People do not know that they are actually hurting someone "unintentionally"
and think that the victims are actually doing fine, doing great.
Perhaps they pretend not to know or just being a jerk.
Every time tried to explain the aftermath is just too late...and it will not help in any form but worsen the situation...why not just go along with it?
Things have changed....
just a fling....

(Some emotions are just being held back and pretended that nothing has happen. Do not show doesn't mean OK.)