How to act after a big fight?

Hi, this is my second post. My husband has ADHD, we found out a couple of weeks after we married. He was tested but still refuses to accept it. He's not taking meds which makes it very hard to reason with him. My question is how do I act after a big fight? I'm asking because it seems like every approach I tried has failed. Before I knew he had ADHD I didn't understand his behaviour at all. So after yet another fight I gave him the silent treatment. That just made him angrier even if he was the one who did something wrong. I rarely burst into tears and when I do it's not guaranteed that it will melt him down either. Depends on his mood. He basically wants me to take the first step since in his mind i'm always the one that starts the fight (wrong tone of voice, daring to express criticism,...). It can start off by me saying something about him not doing or doing something and he takes it as far as treathening to divorce me or leave me, that he never should've married me, that he's tired of me,....Which takes a simple disagreement to a whole other level where it's not about the thing he forgot anymore but about him insulting me.
But of course since I started to conversation I'm responsible for whatever comes next. Ever since we met all he wanted was to have a baby with me. I hesitated at first cause we had already rushed into living together and marriage. After a year and a half, not planned, I get pregnant. He was estatic when I told him. Crying, laughing, screaming, rolling down on the floor, was crazy to watch but he was happy and that was his way of showing it. First days were heaven. Soon the adhd began to kick in again and he fell back in his old ways. I really thought he would've treated me like a queen at least while carrying the child (first child for him) that he so desperately wanted but no...kept insulting me and screaming at me. Afte the first month i started losing blood, doc said I was at risk of losing the baby.
I told him that but even that didn't stop him. His ex girlfriend had an abortion when she was pregnant with his child and he never forgave her. Matter of fact that's the reason they split up. So I tell him I might lose him if I stress myself too much, he answers "I lost one I can lose two" I was baffled. I couldn't believe that even that didn't stop him. I left the house cause I was terrified to see that even his unborn child didn't have an effect on him. Couple of days later I lost the baby. He cried when he heard the news but I just felt nothing but resentment. I didn't believe his tears but I never let it show. I'm losing track of what the post was about in the first place. It's just that there are so many bad memories, so many painful fights, things he said and done. I know I need to let that go, forgive, but it's hard. I was I could say a magic word that would erase my past with him and start again with a clean and pure heart but that's impossible.
I'm not a stubborn person but I feel I give him too much power by being the first one who asks to talk after a fight. Can someone give me some advice as to what is the best approach?

I must say I'm very thankful to have found this site. We're Italians living in Belgium and here there hasn't been much study done about adult adhd. It was even hard to find a doc that would/could diagnose him.

Anyway...thank you for "listening" I'm looking forward to your advice because this is the only place I can talk about this.