So at the end, with the empty circle being Alex-Li, a top of Alex-Li's 'Tree'. Does that mean he ceased to exist.

OR is it like, reality exists apart from our perception, and that we have the ability to constantly change, and that it's like everytime we step forward into an empty room.

Being & nothingness.

and like the other things on the tree, connected to us below us, we are a product of that?