I'm late to this and I know it, but I felt I wanted to add something to this discussion. I think Dr. Wilson added this question because he knows that many have been hurt by how the "church" has responded to a divorce or couples that are having marital difficulties. He wanted all of us to think about how to help someone in this situation. My marriage has been a troubled one for almost the whole 25 years I've been in it because of verbal abuse of me and the children. I've learned over time that forgiveness is the only way to get through and that includes forgiveness of the "church" which includes the entire body, not just the head. There is too much pain involved for the body to be able to avoid also causing pain. I have been incredibly hurt by my church and yet I stuck with my church family and sought outside help for my marriage. In time, my church family through watching me and my marriage actually brought in the outside counselor I had found and it transformed the body. When my marriage faltered again 5 years later, my church body was a little bit more able to support me, but I was still hurt. In situations like mine you can literally split a church because there is abusive behavior, but the abuser professes to be a believer and doesn't think what he is doing is wrong. I can find people to support me and he can find people to support him. The pastor is pastor over all these people - it's a narrow road. I've been at this church for 10 years and I care about all the people there, but the bottom line is that for anyone in this situation in their marriage, counsel has to come from the Holy Spirit and those around the person need to direct them to the Holy Spirit and the Word of God and just let them know that they care. Let the Holy Spirit and Jesus give the counsel because there isn't one of us that can speak to the incredible pain and all the nuances and "issues" involved in each individual marriage. The judgemental approach tends to send people into rebellion, rather than rescue them from it. For me, I have learned to always think about how Jesus would speak and respond to a person before I open my mouth and stick my foot in it.
Sometimes separation is necessary which was touched on briefly. I would encourage all of you to search out the Word on that. A separation with the intent to bring the other person who professes to be a believer back in line with the Word of God, is the step I was finally led to take through Godly counsel and the Holy Spirit. It was incredibly difficult and I lived in 1 Peter during that incredibly hard time, but where there is willfull and continual disobedience to the Word of God, this is a step that may be necessary. (Examples that come to mind would be refusal to stop adultery, physical or verbal abuse).