Hmmm, from the point of view of the people who know you, I think you would be the you they know, at least for awhile. Outsiders would still have their memories of you (the way you were), and they would probably hold onto them as long as your new behaviour fits into the form. I would even say that the people around you, the ones who would have to teach to live again, will, unconsciously or not, (re)shape you according to the old mold they have. If this is true, then you probably would still be you, but not completely. There may be some changes, but in the end people would still see you as they did before the sudden attack of amnesia.
Now, is the person you see yourself to be any more significant or real than the person others see? I don´t think it is, since we are constantly under observation and evaluation. There will always be two sides of you, unless you live alone in a hut in a middle of nowhere.