As a clinical psychologist who has been in direct therapy with 50,000 individuals and supervised over 600 counselors, I have not found that resolving issues of the past does much to help people deal with issues of the present. In most cases I've witnessed, it makes matters worse because it drags the most unpleasant experiences of the past into the present. I know that my perspective is in conflict with many therapists who are trained to treat the past before they can treat the present, but I have yet to see any convincing evidence that this approach is more effective than letting the past stay in the past. My personal experience is that dredging up the past actually increases the risk of suicide and other dangerous symptoms of mental disorders. Another important reason that I am opposed to bringing up issues of the past is that it wastes time. When you could be forming an effective plan and putting the plan into motion to resolve an issue of the present, you spend months, and even years focused on the past while the problems of the present keep building up, eventually burying the client.

In your situation, I strongly recommend that you not waste your time talking about the past. And don't try analyzing your husband. I know that his affair was a terrible shock to your system, and you want to feel closure. You have been terribly disillusioned by what he did, but the best you can do under the circumstances is look to the future instead of the past. Don't discuss the past with your husband or anyone else for a while, and see if you don't agree with me that it helps improve your relationship and it also causes you to be more relaxed. Focusing on the past causes depression, while focusing on the future with an eye to making it successful causes optimism and gives you energy.
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"Some counselors think it's a good idea to "resolve issues of the past" by talking about them week after week, month after month, year after year. It keeps these counselors in business, but does nothing to resolve the issue. In fact, it usually makes their poor clients chronically depressed."

My experience as a Clinical Psychologist has proven to me that dredging up unpleasant experiences of the past merely brings the unhappiness of the past into the present. The problems of the present are difficult enough to solve without spending time and energy trying to resolve issues of the past, which are essentially unresolvable. You can make your future happy, but you can't do a thing about bad experiences of the past, except think and talk about them -- and that makes the bad experiences of the past, bad experiences of the present." Dr. Willard Harley

An analysis of the wayward spouse's childhood or emotional state of mind in an effort to discover why he or she would have an affair is distracting and unnecessary. It takes precious time away from finding the real solutions. I know why people have affairs: We are all wired for it. Given certain conditions, we would all do it. Given other conditions, however, none of us would do it. So the goal of the first step is to discover the conditions that made the affair possible and eliminate them.

One of the reasons I'm not so keen on dredging up the past as a part of therapy is that it brings up memories that carry resentment along with them. If I'm not careful, a single counseling session can open up such a can of worms that the presenting problem gets lost in a flood of new and painful memories. If the goal of therapy is to "resolve" every past issue, that seems to me to be a good way to keep people coming for therapy for the rest of their lives. That's because it's an insurmountable goal. We simply cannot resolve everything that's ever bothered us.

Instead, I tend to focus my attention on the present and the future, because they are what we can all do something about. The past is over and done with. Why waste our effort on the past when the future is upon us. Granted, it's useful to learn lessons from the past, but if we dwell on the past, we take our eyes off the future which can lead to disaster.

I personally believe that therapy should focus most attention, not on the past, but on ways to make the future sensational.