Cutting me off mid sentence

My boyfriend has a habit of cutting off before I finish my side of the conversation. He will ask me a question and as I am responding, without hearing my full response he will continue on with his part of the conversation. The problem I am finding is that when he does not fully hear my full response or receive all of the information his understanding of my words are lacking. As I attempt to clarify, because he has only heard the first part he has already decided for me what my response is.

I realize there is an error in his thinking at this point, but he will ask me to defend myself on incorrect information. Here is my model.

C: Interrupted while speaking
T: “I can’t believe he cut me off again”
F: Disrespected or set aside.
A: Explain further or finish what I was originally saying
R: Very disconnected and invisible

How can I get to neutral on this situation? I can not stop him from interrupting me, but I can control my thoughts and how I respond.