'Yeah, I know it's because I was having an affair'
How the hell do you think that admission comes about?
You think little miss "I have to be true to myself" choked those words out just to appease you?
For what?
It's conviction. Do you know that conviction is the state of being convinced? She knows. Something has caused her to be able to admit to herself, and now to you, that she had an affair and that's why you asked her to leave.
It's a process dude, and all I'm telling you is that this is proof for your logical mind that she is IN one.