At what point in my life should i have opened this letter?

There is no such thing as fear my dear. Don't ever let anything or anyone, including me, tell you otherwise. Or stop you from doing what you feel in your heart is right. Always go with your gut instinct, take chances, never doubt yourself because tomorrow is never promised. Do right by today, do right by you, eventually you will come to see that everything falls into place. 
No other human can ever cause you any damage to you greater than what you can cause yourself. 
We can be our very own worst enemy in life. As we grow up we pick up attachments, demons and fire. We carry those with us, if wer the unlucky ones forever, and with their help we take ourselves to the depths of hell voluntarily. Sounds insane, i know, but with time youl come to understand what i mean.
Steer clear of that girl with the pearly smile, she wants nothing more than to take you to the depths of hell she has seen and dwells in.
Deep down inside, in the most insidious, sadistic place at the core of our personal hell, every lost soul wants to derail anyone that seems to be finding their way out of the maze. Although it may be sub conscience most of the times, misery loves company. 
They can never admit it to another soul but most importantly never to themselves because ignorance is bliss. 
Forever dwelling, always on the go aimlessly. Voluntarily they not only cause themselves to live through hell but drag others along to reinforce their smoke screen. 
This is from generations and generations of brain washing, generations of conditioning, generations of reinforcement. 
Generation after generation people pass on the poison they carry within, like a virus, to other people through connections whether it be blood relation, friendly or romantic connection. Like an olympic torch they passing the poison. As if it were their purpose in life, their goal in life to make sure the beast stays alive.
Without even realising we have become the devils very own spokes person. There has to be a blackout, there needs to be hell on earth, we create problems. We do this to the image we see in the mirror, in our homes with our loved ones, in our communities to our neighbours, in society and the rest of our global family. 
Humanity has become a concept we have lost touch with. Reinforcing darkness to trickle down person to person, street by street, city by city. 
There are bad people out there, like vampires dragging dark clouds everywhere they walk. Just as there are bad people out there are good people too. 

Every being is born with the same level of capability to choose. No matter what life throws at you, you have a choice. You may not like the options and you may question the situation and sometimes create another alternative, but you always have a choice. Its all a matter of choice. Its a matter of persistence, strength, truth, faith and love.
Being open and honest with yourself is a start. Never fear, because the fear is always greater than the  situation. Danger is one thing but fear is a whole different ball game. 
Always love you before anyone or anything else. 
When you can do that you will see what loving another means. 
When you can break free of all the pain and poison around you will you be able to be the immensely bright star that you are. You won't need to look up in the sky for light but deep within. 
You will see the constellations of the stars in your eyes when you look in the mirror. Feel the universe within you. 
There is so much greatness out there and you are apart of that greatness. Dont ever believe otherwise.
Travel because no soul was born to be in one place. We are nomads my beloved. You are your mothers child. Smile at a stranger, because you don't know what a smile will do for that soul that day. Help an old lady cross the road, because one day that could be me. Always be kind, never take less from anyone but i will tell you as my mother told me: hadaa la kala roonanin roob ma' doyo. Respect your elders, be an example to the young ones, always remember what humanity means to you. Wake up everyday grateful for the blessing to see another day. always give thanks for all the blessings you receive. 
Be brave when you need to
Be shy when you need to
Cry when you need to
Because 
you are a hero, you are a human being, you might be the one to save humanity as we know it, if your not at least you can be the one to ignite the fire that does. 
You are therefore you can my dear.