Well she doesn't deserve a gold medal for her part in this, so her feeling guilt is the bare minimum for her actions tbh.
Well of course she shouldn't have done it, obviously. My point is, she did. So either she felt no guilt, or she didn't feel enough guilt to stop her. So what is the point in trying to play to her sense of guilt?
Besides, it's still all deflection from the person who actually broke a commitment, and that's the cheating partner. I understand it's easier to deflect the hurt and anger when you're trying to forgive someone, but that doesn't mean it's going to help you long term. It's actually destructive and prevents the real issues from being addressed and resolved. That's the point most of us are making.
Quite apart from that, it gives the OW too much power. If she really is an evil temptress out to wreck your life, nothing will give her greater pleasure than knowing she's succeeded. You can't make your happiness dependent on her being miserable. However terribly she acted towards you, that approach will simply destroy you. (Generic 'you'.)
Believe it or not some OW do feel bad for the hurt they've caused.
Well then, they're already punished. You don't need to do anything. Again, deflecting your pain and anger is destructive and won't help your situation.
I was quite suprised with something I heard recently actually. A woman in an open marriage was arranging a meet up with a man (aka as bull) ...she checked him out on Facebook first and saw he was married with kids and felt bad.
His marriage is fucked whether she sleeps with him or not. He will simply find someone else and anyway the intention is still there. If you found out your husband was hitting on every woman he knows, and just hasn't managed to get anyone to say yes yet, your marriage isn't secure just because he's been 'faithful'.
If you're relying on everyone but your husband to protect your marriage, there's nothing to protect.