The most likely angle of attack would be privacy law: public disclosure of private facts.

I don't know if this would stand up in court, but it doesn't have to stand up in court if the lawyers can drag it out long enough. In this particular case, that tips in her favor, because the odds of this case escalating to celebrity status are high. That scenario is every corporate lawyer's nightmare, because with celebrity status comes reliable financial support.

If she really was fired, if I were company counsel, I'd be more concerned about the employment law issues vs. the public statement. They did keep the post brief and factual, and I don't see anything actionable about it.