Wrldtrvlr, to address your original question, my best advice would be to try keep this in the open. Express your empathy and listen when he sets boundaries around how much he is willing to discuss, but don't deny yourself a process of healing and understanding. If you love this man and wish to keep him in your life, then you may need to seek therapy for yourself. We can only speak from our own experience, which is validating, but a therapist can truly help you to understand.
Definitely set boundaries around any "acting out" behaviour (like whatever the email indicated) especially if it is hurtful to you, your relationship or to him. Many survivors will continue to abuse themselves with sexual experiences or pornography use because they did not have the luxury of experiences sexual awakening in a healthy, open, consentual manner. Many survivors suffer addictions of all sorts that help them cope, bury the pain or simply punish themselves for their perceived worthlessness.
My husband has gone through cycles of acting out behaviour and the best choice I ever made was to firmly set boundaries around what I would accept within the context of our marriage. I would always love and support him, but I would not aid and abet his self-destruction. I love him too much.
My H quit drinking alcohol 4 months ago and began abuse therapy with a specialist in male sexual abuse just over 2 months ago. After 13 years of marriage, he is no longer saying "he is over it" and he is choosing the steps to find true inner joy. He is getting better at not emotionally detaching, he is getting better with confrontation and he is getting better at communicating. It is such a wonderful process to witness.
Be a good listener, but ultimately you need to take care of you, respect your personal needs and wants and set boundaries around protecting them. I hope he chooses recovery and learns to do these same things for himself.
My very best to you.
I am not your rolling wheels, I am the highway
I am not your carpet ride, I am the sky