I didn't see anything saying that she had her hand on her hip ready to draw, but even if true, so what.

I don't live in a state with these kind of gun laws, but in her state them's the rules. Personally I think getting physical with someone in any way is a big escalation, it's literally a use of force. Force should be reasonably appropriate and somewhat equal, i.e. you don't get to shoot someone for bumping into you at the store (or shoot someone who is not or is no longer a threat, possibly like this situation). You might say the guy had no weapons and simply pushed her, but the fact remains that she returned his force with none. It could have been the case that she got pushed over and then the guy goes to kick or stomp her in which case I think shooting is appropriate. I think the brandishing charge is probably bullshit, because it doesn't seem like she was waving around the gun to intimidate or threaten someone. It sounds like she took out the gun to use it during a physical altercation and then didn't when she realized it was not necessary.

No need to swap genders or substitute ideologically different people, I'm cool with a legally-carried gun being pulled during a defensive physical fight every time. You said that insulting someone is an inherently aggressive action, and sure I'll mostly agree, but the big difference is that it's legal. Insults are fist amendment protected speech most of the time, pushing someone is battery.