I can relate.   I kept pushing my husband to admit that his infidelity was dishonorable.  He thinks that since it was with a man it wasn't really cheating.     He doesn't even acknowledge that it was deceit.  So, in my case, my husband certainly is not racked with shame or guilt. 

I have to admit that my Husband DID feel guilt.  There were many things he did just to try to even the scales, so to speak.He started to "try" to be a better Husband and Father, at the time he was starting to experiment.  Because he had a brain tumor I never really knew who I was talking to.  His lucid brain or his damaged brain.  The first time he had surgery he had a lucid moment as he was coming out of the drugs they used.  He looked at me in utter despair and said "I abandoned you!"  He was coming out of brain surgery so I "ssshhhed" him but I wish I had let him speak!  Would he have told me the whole story?  I will never know but I do know I wish I had a second chance to tell him he did so much more than abandon me and his children!  His treatment of us was so lacking!  The more I think about this the more I seem to focus on the word "lack"!
For my children and I the hardest part of this whole thing is the lack we felt!  On my part, I felt the lack of desire, protectiveness, regard as a partner etc.  He thought as long as he wasn't being disagreeable that was enough!  He could do whatever the F he wanted as long as he wasn't mean.  That "lack" was so much worse.  How do you react when your Husband does not WANT you?  How do you react when your FATHER doesn't value you?  When he would literally turn his world upside down to do for his "friends" what he would not ever do for you? Even though he felt guilt for abandoning us he never felt the guilt of deceiving us!  I feel so much guilt for how I reacted to his "lack".  I wish I could go back and change things.  I don't believe he ever truly saw that his lie was so all- consuming that our family was doomed from the start!  We never had a chance!