To DB you have to get over your emotions. Fear will paralyse you. You are afraid she is going to run? She's already gone. The OM is getting from your wife what you should be getting - time, attention, affection, sex, and energy.
How to bust a affair - confidence boundaries detaching
Go read NOMADS thread to see if they work.
M22,H45,W45 S21/18D12 Retain faith that you will prevail in the end, regardless of the difficulties and at the same time confront the most brutal facts of your current reality, whatever they might be.