Oh man I'm sorry she's done this. What a thing to find out.

I don't blame you for sharing it with her family.

And your thoughts of disabling them well hell yeah! (so long as they remain just thoughts).

I'm sensing a mix of anger hurt and frustration and I don't know what to say.

The fact that you haven't shoved her out just yet, when you could have, well. Does it help somewhat that right now you have the "upper hand" in this situation if she truly does want to stay with you?

Either way, if you two separate I'd suggest you get counselling. And if you two stay together, you'll definitely need counselling.