I am against drug testing my spouse for the reasons everyone above listed. I did, however, in an act of desperation, surprise my AH with a drug test earlier this week and the prospect of me watching him pee into a cup for a test that he knew he would fail made him tell me the truth.
The truth that I already knew, of course. Manipulative? Absolutely. I realized it in that moment, too. It was in that moment that I realized exactly what BigSis said above - it was like a light turned on and I realized that I can not live like this any longer.
My prayers are with you.