This is not the first time this has happened, and it won't be the last. Facebook is too big and way off the path for anyone's good, IMO.

As someone who uses Facebook in a limited manner for a specific topic, I set my audience to public a long time ago. If it's something I can't say in public (on Facebook), I don't trust or allow that information to be on Facebook. Period. There are other platforms for exchanging information that Facebook just cannot be trusted to handle correctly.

As the saying goes, "Fool me once, shame on you. Fool me twice, shame on me."