I hope you understand the fault lies completely in you.
Facebook is know to do or say whatever is needed to further their business. It not a new thing, it is a pattern of deception well documented here on HN.
By choosing to build your business on FB platform you should have understanding, that you are not really building your own business but rather you are building business for FB which lets you build business on their platform until such time they decide it is not worth it and kick you out.
You chose an ally that has no morals and you let yourself be completely dependent on their willingness to keep you.
Every business owner is responsible for thinking for themselves and investigating their partners. If this was your only partner, on which you were completely reliant for your business, it means you have catastrophically neglected your responsibility. Have you done your job you would realize that there is a risk and you would try to save or diversify in case the worst comes. Instead you were just focused on reaping benefits rather than thinking long term.
Pass the message to other people as widely as possible so that public is aware of how FB conducts business so that less people will face the same tragedy in the future.