My wife was diagnosed with ADHD when she high school and has learned to work with it over the years. She is not on any medication.
ADHD does run in her family, both her sister and father have it.
Since our relationship started I have learned more about ADHD than expected and have learned what she needs and how her focus and attention guides a lot of her interests and needs.

The one thing I have struggled with her lately, is that she feels like she needs to explain everything. 
Whether it be the reason we are doing something, how to do something, or the history of a situation.
I am told the point of what we are doing, like getting ready for family to come visit; when I know it has been planned.
I was once told how to change a diaper, after I had been doing it for 3 months, several times daily..
She often tells me about our daughter's experiences, which is odd, because I'm there for all of them and know them as well as her.
Sometimes, I'm the one who has told her about these details.

I know part of it is part of her family's dynamics. The children had to explain every action to their parents; not doing so would get them in more trouble than their actions.
But I do wonder if some of this explaining is related to her ADHD, I know some ADHD folks like to verbalize their thought process to help them work out what is going and to maintain focus. Could this be true? Is she doing this for her own benefit?