45 years since betrayal

My situation is very similar to others...except my husband's affair happened 45 years ago. I was 19 and he was 23, married less than 2 years. I stayed with him and we've been married 48 years. After all this time the only info I got was from his AP. She told me everything, embellishing with Polaroid pictures they each had taken of each other posed during oral sex. My husband has unique tattoos that were quite evident even though I didn't always see his complete face in the pictures. She informed me of their affair and it was still going on at that time. I confronted him and he denied everything. But I knew, putting all together the late nights, sometimes not coming home, always him saying I was with my buddies, drinking and smoking pot. It was always on Fridays and she told me she provided the pot and sometimes speed (the nights he never came home until late Saturday mornings) he picked up beer after work. He always smelled of sex, beer and smoke. So he denied, again saying after a week of work he would spend time with his buddies. It was only one buddy, a f**k buddy. We argued and he left to cool off after my "paranoid accusations." He comes back home late, drunk, and with a hickey on his neck. He admits he went to confront his AP why she showed their private pics and telling me what they do together. I guess he wasn't mad at her because of the hickey and he said they just did some kissing and making out pretty heavily but no sex. I told him what he just confessed to is still cheating and reminded him of our marriage vows forsaking all others. He still denied wrongdoing. I cut my wrist that night. He bandaged me up and said he would stop going over to her apartment if I promised to never try suicide again. One of us kept that promise. Two weeks later he doesn't come home on Friday night. Dee calls me telling me to come pick him up that he is there but passed out in her bed and she can't get him up to go home. I was livid to say the least! I told her she can keep him, I don't want him back! The next day he stumbled in, still in his work clothes, jacket has something in the pocket. I pull out a pair of red lacey panties and a Polaroid picture falls out with it. It is Dee wearing the same panties and my husband takes picture of her posing topless with one hand down her panties and the other hand fingers beckoning the photographer, my husband to come to her. I had packed my bags the night before and saying nothing I leave the picture, panties, and a note that I will not be coming back

I went to my grandmother's house, staying 3 days. On the 4th day he begs me to come home and I cave. He promised he called her and told her he won't be coming over anymore. He never really apologized about breaking my heart but wants us to work this out. I had questions I wanted answers to but he would get angry so I waited about a month, and broached the subject again. He tells me he wants to forget and I need to just get over it. My husband had a serious drinking problem back then, though he never hit me he raised his fist and one time he hit the wall, breaking the drywall but hit a stud and broke his hand. I never brought it up again as I was so afraid of physical abuse.
Several years later, when he had a stroke, he stopped drinking and smoking. He was 41 years old and I had to take care of him as if looking after a child, bathing him, feeding him, etc. I have had many triggers over the years but the last couple of months it has become very bad, a constant flood of memories, pictures I can't un-see, and unanswered questions. I knew what they were doing from pictures and Dee's descriptions (which I guess made it more exciting to share with me). But the answers I asked of my husband have never been answered: What made you go to her? Was I not good enough? Did you think about how hurt I would be if I knew? Did you think of me at all, when with me, when with her? Did you stop the affair or just got sneakier? Did you think of her when with me? Did you share secrets about me and our sex life? I know of 2 things she told me that he thought that I was frigid and only wanted conventional sex. She also told me that he told her he likes perky nipples like hers, not like mine. Both of these comments were similar to what my husband had said directly to me many times.
I have never gotten closure, have never been able to move on. Because of his stroke, he says he cannot remember ever cheating on me so he can't answer any of my questions. He thinks because he drank a lot and did drugs that was the reason, or he would not have ever strayed. My response to that was he may have been drinking and using drugs when he came to see her but he went there straight from work and he wasn't drunk or drugged when he knocked on her door. Over the many years since his affair, things he has said to me that he remembers are things that he and I have done sexually that never happened. He has vivid memories of sexual acts and passion of us together in motel rooms that never happened between us. I assume he was with Dee or some other woman but it wasn't me. In 48 years, we have only been in a motel twice, once after his stroke for an out of town evaluation for SSDI and one overnight stay in Flagstaff a 12 years ago going to see the Grand Canyon. There was NO SEX either time. He has remembered other things that never happened with me. I am almost as devastated today as I was all those years ago and I know I will never get answers from him. He has selective memory. He says he doesn't remember what she looks like, but he remembers where she lived, remembers her husband was his friend and in the Navy, but does not remember having an affair with her or anyone else, even though there was proof. He admits kissing and making out with her one time but that's as far as he can remember. He remembers my suicide attempt and me leaving him but says he does not remember the causes. He apologizes "if" he did anything to hurt me but other than that, he says the past is the past. I say quit bringing up things that trigger my PTSD over his affair then. We just don't talk about it. He says maybe he has a mental block about it though he can remember other things before and after. So we don't talk about it but he wonders why I cry so much, I just answer that I am an insecure, emotional person and I feel worthless. He starts to ask why but then stops...he remembers, I know he does but he will not give me peace by admitting to everything and telling me why. I have told him that by telling me things I want to know will not make me leave him, will not make me mad, that there have been so many years since it happened but I just need closure so I can heal. I will never forget but I can forgive him if he wants forgiveness. I actually forgave him when I went back home all those years ago. He wants me to get over it but he is the one that has the key.