I agree w/Andrew when he says that what you are feeling is perfectly normal. We all get nervous and anxious when we are about to have contact w/the MLCers. Why? Because we don't know what they are going to say or do or possibly give us, i.e., separation/divorce papers. The problem is "fear", fear of the unknown and not knowing what the future holds for us and them.
Breathe! You are mastering the NC fairly well. Now, you need to master the no expectations and learning to accept him for who he is right here, right now. The man you knew has been replaced w/his mirror image. Will he be totally different from the man you loved and married? Time will tell.
You will need to decide what is better for you, i.e., a little contact or possibly little or none. You are the only one that can decide whether it's worth is to get spun up before his visits or not. I know what you are going thru because I went thru it too. I finally decided for my own sanity to go NC and not deal w/him face to face because of what I would go thru.
Coly, I want you to know that you are doing great and you will get thru this. Be patient w/yourself and recognize that your feelings and emotions are getting spun up just thinking about him coming over...why are you allowing his visits to do this to you? What are you afraid of? Can you identify why you get spun up? Are you afraid that you will say or do something that will help him decide to stay away?