Advice on the Aftermath of Leaving

I’m really struggling with the aftermath of my breakup from my ex of 9 years, and alcohol and drugs has been a significant issue throughout our relationship. Since we broke up three months ago, he has gotten heavier into cocaine and alcohol and when he is under the influence, which is quite frequent, he has been incredibly cruel and hurtful toward me. There have been things he’s done and said that I never could have imagined coming from the person I spent so many years with, including screaming at me, calling me names, sleeping with other people at a wedding we were both at, constantly posting stories with other women. The hardest part is that it feels like I’m constantly waiting for the next blow. Just when I think I’ve processed one hurtful thing, something else happens. I feel anxious about what I’m going to hear or see next, and I’m having a really hard time emotionally detaching from his behaviour. I’m trying to figure out how to stop living in anticipation of what he might do next and start healing for myself.