A while back, I had a long chat with my niece, trying to explain what I believe is the inevitability of events and the consequent contradiction of the concept of free will. She puttered off and posted on her page/site/whatever, what was probably a two hour conversation condensed into a short explanation. I post that here to give the benefit of brevity to anyone who is interested.
Things could not be any way other than the way they are.
You made the decisions you did because you used all the rationale and information available to you at the time, so not only were they the right decisions, they were the only ones you ever could have made.
You are a product of the nature and nurture you received as you developed. On a molecular level, chain reactions shaped your biology. On a psychological level, you were influenced by pre-existing family dynamics in your own household and those of your peers. These presets had a single, if complex, possible outcome.
Whatever happened in the past, it happened, and so here you are. Just like you are. It’s not your fault, it just turned out this way because of what went on millions and billions of years ago, setting off infinite generations of chain reactions.
If things are the way they are right now, then things in the future are going to be a certain way too - we just can’t see it. And that’s fate. :)