Yes, the sex-equals-forfeit of the injured mate’s ‘right’ to end the marriage is definitely the WT rule. It is not necessary for the scenario to be one of tacit blackmail (give me sex or I will cheat again) for the innocent mate to be screwed (in more ways than one) by this policy, however.
Wouldn’t it often be the case that in such a damaged marriage, the innocent mate (for argument’s sake, assume it is the wife) is emotionally distraught, perhaps deeply worried about the future welfare of her very young children and her ability to care for them on her own, should she divorce.
Because the family lives a WT style life, there is no money for the guilty mate (in this case, the husband) to move out, so they continue in the same home, trying to move their lives forward on a suddenly crumbling foundation. She does not want to break up her family, and her husband is begging for forgiveness. Yet, she is so hurt, and unsure that she can re-enter into the marriage with any sense of connection.
It all hinges on a single sex act, since she is a JW. She cannot try and see if things can be repaired between them, while reserving the right to end the relationship, if they do not. She must decide to commit before she knows her own feelings or is sure of his sincerity.
If she does what everyone is encouraging her to do and takes him back, even once, she is committed. If she later realizes that the marriage should have ended with the infidelity, then she becomes the home-wrecker, the guilty party, the one the elders condemn.
It’s a shameful intrusion of corporate policy into one of the most painful and delicate marital situations that a couple can go through.