Why?

Things happen and they happen for a reason. But I wonder why they happen at the first place, at least those things which I do not like.
Why I have to separate from my dear ones?
Why I have to listen to rubbish of my boss?
Why do I lose enthusiasm to do what I do not like to, and at the first place, why do I have to do things I do not like to..
I sometimes feel would I have done something differently which would have changed the course of things and would not have lead me to a point where I have to ask myself Why?
There are many things actually that I think I could have done or not done, but Did I knew their outcomes at that time ? No, in most cases No..So why am I irritating myself asking this question? I chose this path cos I wanted to be on this path, and now If there are some thorns on it, then I need to bear them and should be patience enough to reach the end of it. And which path would not have any thorns on it, none.. A ride will never be a smooth , there always will be some bumps and actually those bumps only will make the smooth part of ride worthy to be enjoyed.
So, here I console myself saying, Whatever happens, happen for a reason and whatever I chose to do, I should start it and work till I finish so as not to repent of not doing it at least.