I've seen some offensive stuff. "PTSD is a myth" though?
Like it's been said, sit her down. Tell her that what she's saying is slowing the game down, and go on to say that she is being offensive. She doesn't have to agree, but she does have to have the decency to respect her friends. Currently, she is being disrespectful, disruptive, and that just doesn't work.
"I like you. I might even like gaming with you, if you'd stop kicking down the door every time we try to have fun. Why, just why, are you so convinced that this or that simply can't be? It's not like you've snuck into an R&D facility, heavily armed, and shot down a cybered corpsec grunt before cashing in your paydata. Why, do you think, you know better?"
If she doesn't give a straight answer, something that clicks, explains it all, and lets you clear the air or at least work towards an answer, then she's just not the right player for your game.
I'll tell you now, trying to prove things with real-life facts didn't help. You probably should have tried to get her to immerse herself in SR through suspension of disbelief, explaining that it's a fictional setting, where massive firebreathing lizards fire you for refusing to get a bunch of wires shoved into your nervous system.
Her attitude towards things could have been subverted this way, but at this point, it just plain isn't going to happen.