I don’t think this marriage was TERRIBLE for ALL the years of the marriage. When they got married they were love birds and unless she was a great actress I would say most of the years of marriage was good or she would have wanted a divorce sooner. What I think happened was that the Rabbi’s wife notice she was sad and asked what the problem was. The Rabbi wanting to solve the problem and needed to convince the husband of the seriousness of his actions and told him that this could result in divorce.
Defining verbal abuse is harder, for example, a parent that says ” My house my rules”, is he abusive or just setting down rules. What I think happened is husband said something that the wife found offensive. The wife didn’t convey her resentment to the husband, so it kept happening. Eventually her resentment boiled over and she wants a divorce. What is needed is better lines of communication. The problem is that the parents can’t air their grievances in front of the children and with both parent working it doesn’t leave much private time to talk.