There has to be a part of your ego that is not influenced by others at all. It's not like at conception your brain was designed by Steve Jobs and manufactured by Foxconn. Sure, you pick up a lot of major things from people along the way, especially early on, but the unique brain you were born with must necessarily make your fully grown you unique in turn, I think. Maybe we are "blank slates", but in different shapes and sizes, not identical ones. The margins will be different. Some people will be post-its and some will be like billboards and some like scrolls and such. What I'm getting at with all this is that at least some small part of the mental structure that makes the calls in your life is independent, so it's not impossible for your choices to be truly yours, whenever that small part tips the scale