I know one thing: she is not a manipulative or evil person. She's not heartless. She's just totally lost, confused and desperately trying to keep the balance while she's joggling with my life and our marriage in one hand and relationship with OM on another.
I think that's about right. And it's important for you to know that -- in her current state -- she is NOT a friend of your marriage.
That was the single most depressing thing I had to come to grips with. It's gut-wrenching, realizing that -- to survive -- you have to temporarily treat your wife like an adversary.