It might help too if she knew you didn't consider her having ADD or ADHD a "problem" but see it as a "difference" instead.
Before I was diagnosed I had been treated for years and years a depressed... took Prozac for years because I was misdiagnosed and it never helped... Finally knowing I'm ADD and being treated has helped all aspects of my life. With medication and after doing a lot of reading, I'm able to organize my life, my thoughts and I'm so much more productive.

I believe you dont see your wife as having a "problem" but maybe you could call it something other than that til she figures out it's not the end of the world and there are lots of us out there to keep her company and we're not so bad!

Peg
"It's funny, what the caterpillar thinks is the end of the world, the butterfly knows is only the beginning."