considering the fact that in most cases with cheating, they know what they did or are doing, it's true they will rationalize and try to make excuses. most times if someone has a strong enough will and a seared conscience that's bad enough to allow them to cheat, nothing the victim will say after the fact will ever help. I liken a cheater to an abuser in a way in that the behavior that follows being caught is similar to that of an abuser after they've screwed up and hurt the other person. they will similar to an abuser, go through explanations and or rationalizations much like the abuser will go through being "good" in order to gain the good ground with the victim once again but it's rarely because they want to change, it's just to get out of the immediate pain of being called out on something.

What would be the goal of confronting them after it's all said and done anyway? if it's over, you have to weigh the idea that you know it's going to take it's toll on you again emotionally and likely without a good outcome. it will bring up all the past emotions that already have gone through you and for you alone it will start over, the anger, feelings of betrayal etc. all of it comes rushing to the forefront of your mind and heart again. So if there is a specific outcome you expect, figure out if all of that is worth it. Likely the outcome we expect from such confrontations are not going to happen and we're sstuck with the reliving the pain again.

someone who is capable of adultery in a lot of cases has gone past the feelings of guilt related to cheating. Otherwise their conscience would stop them before going through with it. When the conscience is no longer effective no amount of confrontation usually will change a thing.

silence in my opinion is your best response