I don't get it. I don't get why you continue to view your XH's as victims here. Your XH had a FAR GREATER obligation to YOU not to have sex outside of your M than the woman he had sex with. Your XHs were not strapped to a bed with IV viagra and penis pumps used to force them to have sex. THEY FREELY CHOSE to have an A. THEY are the ones who violated your M agreement, not the women. As far as participating in an A, both your XHs and their partners are EQUALLY culpable, but as far as violating particular obligations TO YOU, this is on the XH. What part of this do you not get????? And, at least in Donna's case, her XH is as guilty of having sex with a married person as his girlfriend. BOTH were cheating on their Ms. BOTH were horning in on someone else's M. Sheesh.
Look, consider another case of betrayal with somewhat parallel obligations. Suppose a mother takes a trip and leaves her H to care for the children. Suppose that while she is away, H has an acquaintance over and together they molested the children. No doubt, a horrible, tragic thing. No doubt, they are both guilty and to blame for despicable actions. But, whose betrayal is worse? CLEARLY, it is the betrayal of the father. He had an additional special obligation to protect his children. Does it matter whether he initiated the invitation to the other molester or whether the other molester called him? I think not. What matters is that the father chose to allow and participate in the molestation. He is AS much to blame for the violations of trust, the harm, the betrayals as the other molester. And he is MORE to blame. I don't see how you can argue that point.
Now, imagine the mother comes home and contrary to this, insists that the father's actions are more forgivable than the other molester's. How wrongheaded would this be? How horrible would this be for the children? Wouldn't this be even an additional harm to the children, to suggest that being molested by their father was less harmful than being molested by a stranger? To deny that it was the father's special duty to protect them is just another horrible blow.
Can you not see that you are in a similar position as those children? You keep putting the greater blame on the person who had no special obligation to protect your M. This is a terrible way to treat yourself. You deny that your XH had a special obligation to you. You deny that his harm to your M was the deeper betrayal. You excuse and quibble over who started the initial flirtation. Ridiculous. And harmful. And deeply disrespectful to yourself.
Affairs happen. A lot. They are horrible betrayals. But they are not the molestation of children. They are forgivable. And if X-spouse's participation in an A is forgivable, then so is the participation of the other person in the A.
Treat yourself better and quit shifting the burden of blame to someone who was far less a cause of the BETRAYAL in your M than your ex-spouse.