Don't bring it up, simply correct her if she suggests it again. That being said the line "someone who would completely tear our family apart like she has"... Sit and think about that for a moment. Sure she made a choice, but you also hand a hand in the erosion of your marriage... Careful pinning this all on her, she simply arrived at a point she made a choice, that's on her... But you need to own your share in the demise of the M too, casting all the blame like that will not suit your cause right? Think about where that is coming from, a place of frustration and anger... It's natural, do not allow that stuff to control your thoughts or actions.