How to tell them you’re leaving bc of emotional abuse?

I had an epiphany this week that we aren’t able to repair any of the issues we’ve been having in our marriage because he’s been emotionally abusive. And now he’s doing it to our daughter as well. I have prepared an email to send to him telling him he’s been emotionally abusive and I want to separate but don’t know how he’s going to react and respond. We need to figure out living arrangements and custody arrangements so I have to live with him for awhile. How did you navigate a similar situation and how did your exs react? Any language i shouldn’t use in my email? Thank you.