Co-worker infidelity...

So my husband cheated on me, with someone we work with. I know I should leave, but I hate the thought of my marriage failing after I was against the whole idea of marriage for so long to begin with. So I'm staying and trying to make it work and we're going to counseling. He said it was just a fling, and theres been no communication for 2 weeks with her. I want him gl officially end it, for 2 reasons. I want her to know its over and I want her to know that I know. He has agreed to this. I dont know what to have him say to her, in front of me, that won't just sound like he's only saying it to appease me. I'm open to suggestions and need them quick. He will be out for surgery soon so we only have one chance to do this before he's off work and she comes back to day shift, which is when I work and will likely have to work with her. Brief note- I found out by seeing messages on Words with Friends of all things. She was using ber sons account and I had messaged her on facebook and asked if that was her. She said it wasn't. But I have more than just his word that it was her.

The first thing that comes to my mind, is "Once a cheater, always a cheater." I know that this isn't necessarily true, but if you work with her, I would be cautious. As for what should be said to her, he should be the one who decides what to say. Make him come up with his own "break-up" speech and make sure he tells you what he has come up with. If you make him tell you what he comes up with, you will know by what he has decided to say whether he means what he said about being committed to YOUR relationship or not. If he makes it sound like he is just trying to appease you, he likely is. If he sounds heartfelt and sincere, I would still be wary for a little bit, but there is a higher chance that he is really sorry about what he did. Also, I don't think that it should be solely his responsibility to say something. You should say something too. Not something catty or a long speech, just something like, "hey just to let you know, my husband and I are in counselling to repair our relationship and I would ask that you please take what he has told you/says to you to heart and accept that what happened between the two of you is over." Just make sure to acknowledge to her that you know it happened, and that you and your husband are going to stay together. In the end if you feel like you need to leave the marriage, leave the marriage. Don't feel bad about having it fail after being against it. Maybe that just means that you had a feeling that something was not right and in this case it seems that you were right. I hope that the two of you can work it out, but at the same time, you need to do what's best for you, not what's best for everyone else in your life.