No hatred here, hon. You both made a mistake, you realise this, and now you can try and look at what caused this to happen and if you're ever in a similar situation again you'll know what to avoid. Sometimes the only way to really learn things in life is to make mistakes.
If there is otherwise nothing wrong with his marriage and it really was a one time thing, I agree that there's no sense hurting other people. You really should talk to him about this, though. Also, don't beat yourself up too much. You know what you did was wrong and you feel bad about it, but there's no sense in continuing to feel bad about something that's already been done.
