Hi Barbie (you strong woman)
I kind of agree with Old pilot on this one. Your H will read and learn when he is ready, might never happen or it will in time, right now it will do him no good or you, you will only get more frustrated.
But I also think that reading and learning about affairs, behavior pattern (explaining why angry, why this arrogance etc.) this will make you understand and maybe find it in your heart to maybe sometime be able to forgive. I'm not saying this is easy, not even saying I would be willing to or able to do this myself (the forgiving part) but I have found that the information about all of this has helped me "understand" the complex psychological effects around affairs and the people in them.
So, when we talk about learning/education/knowledge I think it's the same that I struggle with in school with my teenagers. IF they can't find the motivation in them for learning OR if I can't bring out the motivation, it does not matter what I do. They have to want this by themselves, "bat-sh*t-crazy-mlc" or teenager not so much difference.
Any way, some links I found very educational for me on this subject is on youtube and iTunes/pod radio.
Search for "marriage radio" on iTunes or what pod radio you use!
Also "affair recovery" on youtube. Both of these men (don't remember their names) but they describe how these affair dynamics works.
You could be a little devil and just place a piece of paper with these 2 titles and where to find the info on your kitchen table or some where else, as in not pushing/showing info on him. Let the curiosity in him take over (even if it's you doing little "mummy magic") Think teenager or toddler behavior.
One last thing; As in "why" or "how" it happened, isn't the "why" something he is working out with his therapist? And maybe he is scared that if he tell you the "why" until you feel safe with him or he with you, he is scared that you will leave him? And the "how" is probably the same as someone else wrote, he meet someone as broken as him, mentally broken that is.
I don't want to sound harsh with the above, I know you have made a h*ll of a healing process with all of this, just take my words as input.
Hugs