IF you don't want to save the marriage then by all means go and expose to your heart's content. Take out a full page ad in the local newspaper. Be as vindictive as possible.
BUT if the intent is to save the marriage, and to be able to forgive the affair and move forward, sometimes exposing isn't the right way.
There can be no testimony without a test. I am praying to go through this test and come out the other end with a new and better marriage then before.