but if you knew your fate, it was fate that you got to know it, thus, it was fate that you changed your fate.
fate cannot be avoided or changed as fate is always what ends up happening. just because nobody predicted it and wrote it down doesn't mean the chain of events that set off said event or outcome wasn't present and COULDN'T be predicted before. that's the key, that it COULD have been predicted. a tree falls in the forests and makes noise. observation is entirely irrelevant.
in the end, you only have the illusion of deciding which fate will you chose, because you will make those decisions based on what you will feel when you do. what you will know, what state the world within and outside you is. all those are products of an already present world, so they aren't unpredictable. however, their number is, and that, my friend, is what chaos theory is about.