Attention Deficit Dater:
noun: a condition in which someone has a very short attention span and bores easily when it comes to dating, and moves on to the next person after only a few dates. They repeat this pattern, quickly moving on to dating someone else, and yet again, becoming bored.
Guy: "I'm not sure what happened to Sandra. We went out for three dates, and everything was great, and I haven't heard from her. I saw her last night with Jim."
Girl:"Don't sweat it. The girl's got ADD."