It sounds to me like your wife is using the elders as a substitute for marriage counseling. You might try explaining to her that this cannot work because they are not trained in that area and are limited in their functioning to matters of judicial concern and religious loyalty. A good marriage counselor may help clear things up in your marriage and eliminate the need to involve the elders.
I agree that the elders were out of line sharing your personal info with others. You could bring that up with them, but I don't know if it would help or hurt your situation.
Your desire to stay connected to your family is totally understandable. Many here, including me, have lost members of our families because we left the WT. Maybe a fade would work for you. It is usually more desirable than DAing or getting DFd if you want to maintain contact with JW family. There are some on this board who continue to associate with the WT while knowing that they are not "the truth." They do this for various reasons, including to keep their family intact. This may work for you, or not. Only you can decide what's best for you.
As far as cults are concerned, the WT defines a cult as a group that follows a human leader. This is a very self-serving definition on their part. It also does not address the fact that they started as a group that followed Charles T Russell. Others would define a cult as an organization that uses manipulative practices to attract and maintain membership, and employs certain techniques that limit and control their members' thinking ability. By this definition, the WT is a cult. You can explore this possibility further by reading books on cults written by mental health experts, such as Steven Hassan's "Combatting Cult Mind Control."
Best wishes to you and your wife.