You may want to eventually reply "Look, I'm only going to say this ONCE. I simply decided that I'm no longer willing to lie to cover up your affair. These are just the consequences of what you decided to do, that's not on me, and I won't own it. This is your mess; you get to clean it up. The sad thing is that it's affected a lot of other innocent people, who we both love very much."
But I would only do that ONCE -- I wouldn't get into a text message tit-for-tat. And something close to what I suggest here as a script WILL cause her to SPEW, so put on the big-boy raincoat!!
