Sorry for your loss fella,
It's going to be hard for every one who knew him and shared his life.. you'll feel empty inside at losing him so early in his life and your shared friendship.
If, as he sounds from your post he was an outdoor, live life to the full kind of guy then at least when he went it was doing something that he proberly loved.
hang onto that thought and keep him alive inside you with the good memories of times you had together, at first this will make you cry and feel sad but over time it will make you smile and you'll be able to share those smiles with other people who knew him like you did.
RIP Alex.