空城梦魇躲不过空梦一场
[kōng chéng mèng yăn duŏ bù guò kōng mèng yī chăng]
It is derived from the loneliness in an empty city where people feel haunted (梦魇 refers to nightmares or being haunted) and realize that all this ends up being just a dream they can't get away from (meaning they're doomed to return again and again to their own bad situation or memory). The term implies the despair and powerlessness people feel when faced with unchangeable situations, like the pain caused by broken love or losing a loved one.