@Eliusa,
Quote: How is it 'honest' to tell someone you had been dishonest?
If you have to even ask this question there is no point in my trying to explain it to you.
Quote:I think it is more honest to not to hurt innocent person with information that can be withheld (otherwise hurt him for nothing) and try to not to sin again and pray that he will never find out.
And that is fine. I can totally understand that thinking and in fact I wrote that it may well have been the best way to go.
Yet I believe honesty is a key building block of a healthy relationship. And guilt can be a burden on an individual. So I understand why someone would want to be honest with their partner and come clean as it were, with their transgression. Of course, one would always run the risk that their partner would see the infidelity as a deal breaker. But then we get into accepting the consequences for our bad choices, something the OP may find out. But at least she will know that she was honest with her partner and that may allay her guilt to some degree.
Honestly, if my wife had a one time fling with someone, I think (I said think, mind you) that I would want her to tell me for several reasons which I don't think I will enumerate here. Whether I could get past her infidelity is something I don't believe I could honestly answer and would depend on several factors.