When you add profiles to WikiTree is ceases to be YOUR tree. It is a ONE-WORLD tree. That is the whole premise of WikiTree. We are all part of the same huge community with connections to each other. You may not want to participate in WikiTree any longer, but there are others who will connect to your profiles over time. Your work immortalizes your family.
If you haven't read this, you might find it helpful: http://www.wikitree.com/wiki/How_to_use_WikiTree