I really liked this post and found it very thought provoking.
I'd also like to congratulate @Sucky for creating his first intellectually stimulating thread. 
I guess I would ask: why stop measuring the "series of events" at the moment in time when you got on your motorbike? (Sounds like a horrible experience btw, hope you had a full recovery).
Isn't it necessary to rewind even further back rather than picking an arbitrary moment in time as the start of a "sequence"?
For example, you could go all the way back to the moment you met your then girlfriend and undo that moment, which would in turn undo all subsequent moments stretching across months or even years that led to that 'fateful' night when you got on a motorbike?
Or go back even further to the area you grew up in and all the social, parental and educational influences you experienced in your life that made it more likely that you'd find a certain type attractive? Undo some or all of those and you could still go to the bar/wherever you met that girlfriend, but you'd never have even asked her out b/c your parents raised you in a different way or your peer group was different so you didn't find her appealing. Same end result only this time measured across decades: you don't get on that bike on that evening in that area.
My admittedly limited experience has been that people tend to invoke 'fate' or similar when they want and/or are struggling to make sense of a particular chain of events. Sometimes we do this because we crave a semblance of meaning or control in our lives. Sometimes it is a way of coming to terms with loss or coping after trauma. We see the patterns and sequences we want to see, nothing more and nothing less than those patterns that are useful to us and don't destroy out inner lived narratives.
The reality is it is impossible for any human to truly trace any sequence leading to any event, as there is no way of knowing which events in which chains in which moments combined to make the outcome we are grappling with more likely to happen.
I think people use religious ideas in a similar way. Bottom line is we are all trying to make order out of chaos and if it brings us inner peace or we can learn a lesson from it, we'll draw a pattern.
I'm not saying that's a bad thing by the way. On the contrary I don't think we'd be able to survive otherwise. I just don't think claims of 'fate' or the like have any ground to stand on.
