When you look to the past, don't sit and dwell on your regrets. Instead, focus on the things you learned from each experience and how they may enrich your future. Use the past not as something to hold you back, but as a method for reaffirming the drive to move forward on your chosen path.
What am I to choose? "Choose what you please, as long as you choose. " There you have a foolish answer, which seems to be the outcome, however, of all Dogmatism, which will not allow us to be ignorant of that which we are ignorant.