You have my sincere sympathy in the recent loss of your Brother. He was only 18? Way too soon gone.
The poem that you wrote could be perfectly written by me for my Youngest Brother(Type 1) who was 2.5 years older than me. He died in 2005 and although his leaving has become easier, there are still times when I miss him soooo Bad. When we were younger everyone thought that he and I were the Twins also, although it was my older Brother(Type 1-died in 2003) and my Sister who were actually the Twins.
It is still so early, let yourself grieve for your Wonderful Brother. It will get easier. You know that he loved you Dearly. Thank you for writing this Wonderful and meaningful poem.