Exciting and refreshing OM and clingy enabler husband.
Why would she quit the A?
Give her what she wants.
"I won't share my wife with another man. I respect your choice although I do not agree with it. I will no longer be the backup plan for you. My job is to lead this family. Your choice is either to stay or go with OM. There is no middle ground. I don't need you when you are disrespecting this marriage and family."
Then get your ducks in a row. Focus on your own needs. Physical, financial, spiritual and emotional. Make a plan for all possible outcomes.
It's called parallel path.
Leaders are not leaders because they choose to lead. They are leaders because people choose to follow their lead.
Man who leads his own life and his family is attractive.
If she notices that and respects you for your decisive actions, she may follow. If not, you will be better off to move on and let others admire and respect you.
Your marriage as it stands is dead.
It's time to change dynamics and stop doing what isn't working.
You must never confuse faith that you will prevail in the end—which you can never afford to lose—with the discipline to confront the most brutal facts of your current reality, whatever they might be.