At the highest plane all is fixed. However, in this world, which is what concern us, fixity and freedom walk together. We have our role in determining our fate, at least to some extent. This is so because we carry within us the divine element which is potentially beyond the law that governs the world. The closer we draw to this divine element within us, greater the power we exercise upon our fate.
As to Death, there are certainly periods of time during which there is a great vulnerability and possibility of death even if the body is apparently healthy. But it is not definitive. If one can pass through this period then once again a window opens during which life seems to sail relatively smoothly. What is needed most during these critical vulnerable phases is faith and endurance.
Each soul is on its own unique journey and all associations however beautiful come to pass in this world. However, whatever is rooted in some deeper truth of our being tends to return until its deep purpose is over.