Well why not ask if symptoms happened after all the concussions or were they always there? Maybe the concussions happened before you relationship but may help here to clarify. I have NPD and have worked on myself for sometime. One said above about seeing a trigger and being able to modify. This is true however for some the realization can also come after it had happened. I at times do or say something then realize after it happens that I am wrong. What I'm getting at it for some the way to repair is different. The important part is one knowing and accepting when they are wrong.