Why do i still feel like ****?

my nephew was killed october 24, 2009 by a guy that he trusted and he even got in the car with him and he doesnt do that with anybody but somebody he doesnt trust.He was 20 years old and im 16 and he was like a big brother to me and i took it pretty hard and it still feels like the first time they told me. We were really close he always looked out for me with guys and eveything else and took me places and did things with me and taught me things and its hard to realize that hes gone and hes not coming back he was so young and he helped everybody out and was there no matter what u needed. He was killed because of drugs and gang violence. But i dont understand y when its been almost a month that i still feel like **** i dont understand why it had to happen to him and why not somebody else that wasnt so caring and sweet and funny and didnt have a kid to raise and no resposibility. I just wanna know how long it will take for me to not feel like **** and to be happy again. It feels like everybody else in my family r fine and r back to normal and doin ok and i still feel like **** i just wanna know how they r doing it. I think about him no matter what i do or say everything i do every decision i make i think about him and it changes everything. and i guess thats good but it hurts whenever i think about him i helped out with everything with the funeral and the burial and i helped cook for the dinner to celebrate his life but every time id turn around id be crying and i still cry all the time and ive had time and everybody else smiles all the time and is happy and i still cant even play pool with out thinkin that he was the one who taught me how to play pool i just wannna know when ill be happy again and not hate god and the world for taking the best person i know away from me and my family i just wanna be happy again so if you have any sugestions please let me know cause i wanna go back to hangin out with my friends and bein happy and everytime i try i just end up goin back to my room and cryin and i just wanna be happy please help me cause it seems to me like ive tried eveything. My best friend has tried to help me and most of the time she ends up not leavin my side and just sittin with me and held my whenever i cry and just watchin movies with me for the past 4 days after school so would some one plese help me cause it hurts really bad. I feel like im the only one who feels like this.