Also - let me just say, don't jump to any conclusions.
By your own admission, you have just begun making changes, and things are going well. But it would be foolish to expect that your wife immediately trusts your changes are permanent and dumps the OM.
She is probably going through a time of confusion, and it may not serve you to bring up the affair quite yet.
What if you KNEW that this meeting with OM next week, was going to be her opportunity to tell him it's over? Or, what if you knew that she was going to see him and he was going to suffer by comparison to the new you, thus leading her to break it off?
Either of those scenarios are possible. You may want to be just a little more patient and see how things pan out.