Even when we have realized oneness and nothingness, we still have our personal lives to manage, bodies to take care of, and mouths to feed, and you will know which one is yours and which ones are others', so you won't put food into another person's mouth when you are hungry. Also you won't kiss a rattlesnake or hug a cactus no matter how strong an affinity you feel toward them. But at the same time, we know these apparent separations are functional, not fundamental, and should be recognized as such without mistaking one for the other. I would call this apparent separation "functional ego," or you can call it your "character," which is the collection of your beliefs, habits, and other people's expectations.