"It was such a crazy time, and I didn’t want to have anyone worrying about me, especially Mitt. I didn’t tell anyone, but I knew I had to quit."

Said Ann Romney, speaking about last spring.

"I started feeling tingling and a little bit of numbness coming back and I was dizzy, I started to get dizzy, the dizzy head, you caught the MS fog, the real foggy brain."

Stress triggers flare-ups, and the campaign, she notes, laughing, is a stress.