Why is Facebook allowing people to spread viscous damaging rumors that are false?

My Fiance's picture has been repeatedly shared on Facebook by people writing false information about him. I have reported the matter to facebook but apparently they see nothing wrong with someone spreading vicious rumours that are damaging to a persons reputation. Below is what I received from Facebook so how can someone spreading false, viscous and very dangerous rumors not be something that degrades a persons character? We don't allow things like: • Descriptions or photos that degrade someone's appearance or character • Targeting someone with threats