Dre,
I am going to tell you a little about my soon-to-be xH of 23 years because it has some relevance to your story and a couple of others here.
We were very sexual before marriage and it was good. Once we were married it dropped off considerably and it was only when we were trying to get pregnant that it picked up a bit. During the last 10 years, it would be only once every month or two and quite often he would lose erections during intercourse. Toward the end, he would not let me touch him at all and would basically masturbate himself to an orgasm, only engaging in intercourse right at the end. He had all kinds of excuses for this, but did not feel we needed to seek counselling.
After I found out he had someone else he was interested in (he only admitted to being sexual with her after he moved out) and we were in counselling, he finally told me that for many years he had been using pornography and masturbating rather than being sexual with me. I was in complete shock. I only think he told me in the hopes I would choose to kick him out rather than him having to leave on his own (looks better to family and friends). I, however, did not do that and was willing to work to save the marriage. During the 6 weeks we were in therapy, he quite suddenly became very interested in having sex with me and during that time we had more sex than in the previous 10 years. This was very baffling to me when he then just up and walked out while in a joint therapy appointment, 2 days after our last sexual encounter. My therapist (who was seeing both of us at that time) explained that he had already determined that he was leaving and the counselling was just another ploy to look good. Once he knew he was leaving he could view me as something other than he wife or mother (he got those roles confused) and I became a play thing. He wanted me to look and act like one of the women in his porn videos and since I was desperate at the time, did exactly that. I look back on that time with great pain and humilation and know that he truly enjoyed taking advantage of me like that.
He is still (I think) in a relationship with a married woman that he started seeing while we were still together. My therapist says that in addition to being an N, he is also a stage 1 (last I knew) sex addict. He also feels that there is a good chance he will take it to higher levels now that there is no one around to monitor his behavior.
I'm not sure how all this fits into somatic vs cerebral, but the bottom line is that you do not want to be in a relationship with someone who has these issues. Had I known years ago what was going on with him, I would have made other decisions if he had not been willing to seek help. Forever more, I will wonder what he has done that I don't know about, but I'm probably better off being kept in the dark.
Good luck to those of you still trying to work through this.
Brigid