I just want to say that Im glad you stood for what you believed in about her, but don't take on E's issues with her. Its up to E to figure that out. Im assuming he is a full grown man and he'll figure out that she is using him in the end. Taking on another persons 'problems or pain' does you no good. Its ok to sympathize, but don't dislike someone bc you think they are doing something to someone else (esp when there is no proof of that yet). Its just not worth your mind time.
One thing is clear, you do not need her negativity clouding your life and mind. Your speech to her will definately keep her away from you! And that is great! Your life does not need her in it. E & Mike can have their friendship that does not need to include you & her! Soooo good for you for taking yourself out of a dreadful future situation now... its not worth your time and energy to worry about 'the next time' ...