I know that this must be tearing you apart inside, and I wish that my words could somehow make this awful feeling go away. I think you would be atypical if you didn't somehow feel that your husband were seeking out men and, as a result, rejecting you.
Unfortunately, this is not how it is. Your husband's preoccupation with looking at other men is NOT ABOUT YOU. In fact, it's not even about sex. Because of his childhood sexual abuse, he is battling a lifelong identity crisis. When boys are sexually abused, they often dissociate--even if they derived some pleasure from the experiences. (In fact, the elements of pleasure and secrecy ratchet things up a couple of notches.)
Sexual abuse is about power and control. Boys who are sexually abused suffer powerlessness; I suspect in the way that women who are raped experience it. Often victims spend the rest of their lives trying to win back power and control for themselves.
When male victims of SA become preoccupied with men (and the male physique), they are trying (in their own explicable way) to recapture their sexual identity, often longing to look like or "be" the attractive, macho have-it-all-together man that they feel (or have felt) incapable of being. I know what this is like....this is my story. More than anything in the world, we want to look - and be - "normal." The trouble is, we had that opportunity stolen from us the second we were molested, and most of us spend the rest of our lives desperately seeking acceptance and trying to find our place in this crazy world.
I realize that this may be difficult to relate to or even understand. In fact, I have only recently begun to understand this for myself. What your husband is experiencing (and what you are struggling to understand) is really not about wanting men instead of you. He doesn't really want to sleep with other guys. He is in search of the "guyness" within--and he doesn't know how to find it. At some level (and I don't expect that you will necessarily understand this), he is hoping that this male part of himself will jump off the page or from a web site...making him whole.
The double whammy (and I struggle with this continually) is, of course, that no pornography, no web site, and no stolen looks at other guys can, as I sometimes say, "put Humpty together again."
From the things that you have written, my belief is that your husband wants more than anything in the world to be "normal," to be perceived as the in-control, desirable male that he is has been so frantically longing to become.
For better or worse, you have chosen to love a man whose attention and energies are split. From your previous posts, I recall that you say he is a good person with many wonderful attributes. He is probably working overtime to try to love you and meet all of his responsibilities in this committed relationship while trying to manage the inner conflict that I have described above. I can tell that you love him very much, and I have interpreted your own inner conflict as frustrating, and, perhaps, fearful.
My bet is that your husband is not planning to leave you...and, in fact, it is probably his biggest fear that you would leave him. But you have a history together, and my sense is that you don't really want to give that up.
The challenge that I am facing in my own life is learning how to live with my demons and to balance and enjoy my wonderful wife and kids....all of whom I love very much. I have been struggling with this stuff for all of my life...and I have only (in the last few months) begun to understand what's really underlying all of these feelings, fantasies, longings, and disappointments. I've already come to grips with the fact that (at age 53) I'm not going to "fix" this (whatever "this" is!), that my longing to be "normal" is a wish that will go unfulfilled, and that my best shot at happiness is to make peace with myself.
One thing that you may wish to consider is printing out this post and sharing it with your husband. If he is struggling with what I think he is struggling with, he can probably identify with much of what I've written here. And part of the healing process for those of us who are victims of sexual abuse is when we finally realize that we are not alone with these feelings of inner turmoil and disconnectedness.
I encourage you to focus on the things in your marriage that are working and on those characteristics that your husband possesses that were attractive to you in the first place. As a psychologist once said to my wife and me, "It's no accident that you found one another." My sense is that you are in each other's lives because you have wonderful gifts and lessons to share with one another. Focus on those and see if you can put these other feelings of inadequacy in the background (and keep saying to yourself, "It's not about me....It's not about me...."
I know that I have rambled on and on here; I only hope that at least some of it makes sense.
Good luck...and welcome to the club.