I have just read your post and the thread that follows it.
First, I see that there is a mixture of advice, some of which is consistent with DB philosophy, some perhaps not. If you really want good legal advice, go to a family law attorney. If you want to maximize the chance of saving your marriage, however, keep reading DR and getting support and input from this site.
One of the patterns I see in many of the responsive posts is to play to your anger or pride and have you firmly show your partner that this infidelity will not be tolerated - by taking firm and immediate action. I would encourage you - because you are stating your goal is to save your marriage - to avoid rash actions of any kind that are based on emotional impulse, even though the temptation can be very strong.
I believe you are on the right track. I sense there are two critical things for you to work on at this point. The first is not to pursue. It sounds like you are already working on this. Keep this up and don't get discouraged. Since this is such a difficult thing to do, you can't expect immediate perfection. Keep trying, and credit yourself with success for every minute or instance you are able to do this. The more you do it the the more confident you will feel as long as you don't berate yourself when you "slip"!
Secondly, absolutely, positively do not get into the same old arguments you've had in the past! If you succeed in disengaging from pursuit, you will have extra time to sharpen some of your other DB skills so that you can more successfully approach such topics - when the time is right! For now, it's not.
If you can really make progress on just these two things for now, I believe you are doing the best things you can do at this point in time. Also, bravo to you for seeing this as an opportunity to make yourself a better man. I am confident you will.
