Even when it is repeated, a relationship of sexual convenience without the feeling of love is relatively easy to stop when it is exposed. That's because a relationship without love is usually not an addiction, although it is still devastating to the other spouse when it is discovered. But it's difficult to know whether or not a relationship is an addiction until a husband has left his lover for good. A husband may claim that he does not love his cohort, as a way to deflect attention from the relationship. Then when everything is back to normal, he gets back together with her.
Addicts are notorious liars, and sincerity is their specialty.
An alcoholic that I once counseled told his wife that he had simply made the decision to give up drinking. He was convincing for two years. But one day, he was rushed to the hospital for drinking automobile window washer fluid. It seems he had been adding blue food coloring to gin, and stashing it away in a window washer fluid container. Unknown to him, his brother had filled the container with the real thing, and he just about killed himself drinking it.