Thanks for the help PDT, I'll do as you say and put off any discussions this weekend. I'm definitely not moping and will put on my best face when we do talk.
As for the 3rd party discussion, that was exactly what I said yesterday; "you end the affair immediately and never communicate with him again and we might be able to talk. Otherwise, you are not welcome in this house because I will not be in an open relationship". It might have worked because she has closed all but her "secret" email accounts today (although I can't say she hasn't opened others). Time will tell....