A few suggestions -I think you can't keep bringing up OM. Or work out a specific time period when you can ask questions and she needs to answer. If she's evasive, you might have your answer. -I think you need to free yourself from this fear you have. Sandi hit the nail on the head when she said you were basically reacting out of fear. Her threats and emotional blackmail only work when you are afraid you'll lose her. -In that vein, you should try working to get more independence from her...at least emotionally. You need at least some level of detachment. You need to know you'll be okay.
-In your wife's defense, I do think she's probably trying. I do think you have to limit your lack of trust. What's the worse that can happen? She'll cheat again? If you get strong and know you'll be okay...then that shouldn't crush you. I also put myself into your wife's shoes regarding my own job. I wouldn't leave it because my wife told me she needed me to.
You cannot be lonely if you like the person you're alone with. Dr. Wayne Dyer