I know your first inclination is to put a stop to the EA, but as others have said you cannot control another person's actions. The sooner you can concentrate on yourself the better.
Trust me, I know this is way easier said than done. For me, I tried to ignore it but got to a point where I couldn't take it anymore so I kicked him out of the house. Felt so good to take control of the situation and show him I meant business when I said I would not tolerate it.
You have to overcome the fear of doing something that will push your S away forever. It took me a while to get there even though others were telling me to kick him to the curb. I had to really know that it was the right thing to do. When I felt that in my core I swiftly took action and haven't second guessed myself.
It's been a month since I kicked him out. We have had hardly any contact, only business things. He's moving into an apt this weekend and out of the blue yesterday he says he wants to know if there's any hope for us. I'm not saying that happens for everyone, but being strong and maintaining boundaries is good for you no matter the outcome.
Way to go Pearl, you showed a lot of strength - that's how it's done. Setting boundaries with how people treat you tells people that you respect yourself enough to let go of the people in your life that don't respect you.