Living, to be true, must be purposeful. You must have goals to reach, ideals to strive for.

If you fight shy of obstacles, then you can do nothing worthwhile in life. You can at best vegetate, but that is not living. Living, to be true, must be purposeful. You must have goals to reach, ideals to strive for. And goals cannot be reached without encountering opposition. Such opposition should not upset your peace of mind, but should strengthen your will to fight the battle of life heroically. It will be possible if you learn to accept these opposing forces as an inevitable part of phenomenal life, as unavoidable evil.
Never regret. Learn the lessons from your past experiences. Remember the lessons. Let the lessons guide your future actions. But do not brood over the past. Do not regret "If I had done that, I would have become this... If only I had."—it is all futile thinking, waste of time and energy. Because worry depletes energy. Does nothing more. The fact is whatever happened was destined to happen only that way. It could not have happened in any other way. Everything, from the tiniest movement of a particle of the mightiest disturbances in the universe, everything in the past, present and future, every cause and every effect, has been ordained in certain way by the omnipresent, omniscient and omnipotent Will of God. Things happen as they are destined to happen. Whatever will be will be.

No man has the power to alter the course of God’s Will. Que sera sera is eternally true, universally true. To regret, to brood is to show your cowardice in the face of the inevitability of events and to disturb your peace of mind for nothing. Wisdom lies in seeing the working of God’s Will in every happening and remaining at peace with yourself and the world.