OP, I'm so sorry.
Yes, you're feeling the typical emotions. At some point, numbness will go away and rage will take over. Then you will process it. The hardest part is that you will get NO explanation from him that will satisfy you. Because it doesn't make sense to a normal, empathetic person. You have to accept that he has a wholly different way of relating to people--one in which deception and self deception is second nature.
The story reminds me of someone I dated years ago, who then started sleeping with my roommate, so that ended, but we stayed in the same circles. Years later, I knew another one of his exes, who lived in Europe. They had been together for a couple years, she was his first serious love, etc. I also knew the woman (fiance) he was living with, in the US. One day the woman in europe called me to ask if I had heard from him. Evidently they had gotten back together for over a year, and they were supposed to meet up to go to Italy for a ski trip (he traveled to europe every 6-8weeks), and suddenly he didnt show up, didn't call, didnt answer phone or email. Because his US girlfriend decided to go on his work trip this time. The 'ex" was livid: they had been talking about her moving to the US, doing a second degree, marriage, etc.
I told her about the woman he was living with--she said, oh, yeah his housemate. No, I clarified, his fiance--they had a big wedding planned. She went ballistic, of course, and I even got in touch to tell him what a scumbag he was, and that he needed to tell his fiance. He denied the whole thing, called the "ex" crazy and vindictive. He ended up getting married 2 months later in a small family only wedding and they have 3 kids and I have no idea whether he is faithful or not. Kind of think not, since I think he's pathological, but who knows.
The thing that really really shocked me was that some of his (male) friends knew--they didn't approve, but they kept quiet. One of them was a good, mutual friend of the "ex" (but they stopped speaking after she realized the betrayal). I wrestled for a long, long time about whether to tell the fiance (whom I didn't know at all). I instead just told off the guy, but figured that he would just put a spin on things, as he tried with me, that his ex was hysterical, jealous, etc. To this day I wondered if I should have said something to her. It was horrible enough confronting him years ago, after what he did to me, but now that I'm married with kids, I wonder.