Holding it over someone’s head would be wrong. But other scenarios are possible.
In a normal relationship, without JW rules, the wife may continue to sleep with the husband in the hope that their relationship can survive, but discover within a few weeks or months that they cannot remain together. In this scenario no one has held anything over anyone’s head, they have made a genuine attempt to remain together. The only problem is the price the JW now pays for separating is to remain single and wait until they become “free to marry” if that ever happens, through no fault of their own.