I don't believe in predestination. However, you have to admit that it's a pretty comforting idea.
Think about it... If everything really happened for a reason, and we are all just heading along a path of destiny, there's nothing to worry about along the way. What a liberating view point! If I thought that way, my breakup with my ex-girlfriend, while sad, is not really a big deal because it was meant to happen anyway. Now I regret the things I could have done to save the relationship. However, if I look at it from the perspective of we were never meant to be together, I would think that no matter what I did, it was going to end anyway. I wouldn't have to worry about finding a new girl. If I was meant to be with someone, I'll eventually find that person. If not, then I'll just be single.
Most people desire to have more control over their own lives. I actually desire less control. The knowledge that ultimately I control my own destiny puts too much pressure on me. Right now, I'd just love to hand the reigns over to someone else and go along for the ride. No pressure. No worries. No regrets. The notion that everything happens for a reason would allow this.
It's too bad I don't believe this. I think I'd be happier.
On a related note: I swear that the happiest people in the world are simple people. There's this one woman at work whoe comes to mind. She's and almost 70 year old clerk. She's dumb as a brick. She may very well be one of the dumbest people I've ever known. She's very nice. She's just stupid. However, despite her intellectual shortcomings, she's very very happy with life. She's been married several times. She has seemingly a thousand grandchildren who she loves to spoil. She doesn't worry about politics or the issues of the world. She's simply happily oblivious to everything.
Then there's me... I overthink EVERYTHING. I write hundreds of pages in this blog searching for some existential meaning. Even when things are going well in my life, in the back of my mind, I'm constantly worried about the impending oil crisis, global warming, the economy, health care, the needs of the poor, etc.
Unfortunately, there's no way for me to suddenly become oblivious to the world around me. I can, however, pretend to believe that I serve some kind of purpose in this world that is beyond my control. When I look at things that way, my life almost makes sense.