Confused about "destiny"...

After watching the movie Slumdog Millionaire, I have a lot to say about the idea of destiny. So, the whole movie is supposed to be centered around the idea of destiny, and things being meant to be. Jamal is destined to be with Latika through a series of events that unfolds throughout his life, and in the end he wins the girl. He credits this all to "destiny". This is confusing to me because it seemed more like it was Jamal's choice, rather than his destiny. It was his choice to pursue looking for her. It was his choice to stay a moral person. Is it still destiny if it is what you choose?? Because I thought destiny is predetermined, which would mean that technically you cant choose it, if its already predetermined. Jamal could have easily abandoned Latika, become a gangster like his brother, and he would have become much more wealthy. So, maybe the fact that he chose the harder route is a reason to believe it is destiny. I have always believed that if something is meant to happen, it will happen and you will have no control over it. If two people are "destined" to be together, then they will somehow randomly bump into each other on the street corner. This is completely against the turn of events in Slumdog, because throughout the whole movie Jamal is searching for Latika. That being said, im beginning to think destiny isnt so simple after all, and it has many terms and conditions.