Whatever happens, happens.
To a degree, in our lives as each moment passes and different circumstances come to past, we have to realize that after they happen, there is no way to change them. We must take life for what it is, a series of unpredictable events ultimately out of our control.
Sure there are ways to prepare for life, and understandably doing things such as setting goals and making a game plan for your life will take you to new heights, even to places you would of never imagined being. But life is too, very unpredictable.
We never know when our lives will end, and we cant stop things from happening a lot of the time such as accidents, and other fortunate and unfortunate events that life will throw at you.
So we must deal with our lives as they come to us, preparing for the future, with the outlook on life that not everything will go as planned, we must adapt to survive, and thrive.
We must also be willing to move on from our pasts whether good or bad in order to keep up our lifes journey towards being happy.