It is heartening how valiantly people with undiagnosed ADD try in the face of their despair. They don’t give up. They keep pushing. Even when they’ve been knocked down many times before, they stand up to get knocked down again. It is hard to keep them down for good. They tend not to feel sorry for themselves. Rather, they tend to get mad, to get up, to have at it again. In this sense one might say they are stubborn: they just don’t give up. But they may remain depressed.