How to deal with the OM/OW

[PortlandDad]

I posited this question in my other thread, but I wanted to open the question to a broader audience with a topic of its' own. I'd like to hear how others have dealt with their Sp A partners. What tactics have worked best in retrieving your Sp from the clutches of an AP, and what hasn't worked at all. Do people here advocate confronting the AP, or avoidance? Which is more dangerous to a marriage: an AP that aggressively works to dissolve your M or one that is a "good listener" and is otherwise passive?

I'd love to hear any and all perspectives on this. Thanks!