My best friend killed himself

Hello, I dont really know how to kick this off or where I want this post to go or what it will do, I just have to air all of the past months. My best friend recently decided to end his life. He was the one i could turn to no matter what. He gave no reasoning and left nothing for us left behind. It came out of the blue. I was with him partying the day before it happened where i almost killed himself after chugging massive amounts of alcohol. It broke me, I am truely devestated. I was the one who reported him missing after he didnt show up for school and i spent the rest of the day searching for him high and low. They found his car and a weapon later that day. He fell into the sea and he is still missing. I didnt realize he was gone for about a month. I couldnt sleep, eat or live a normal life. I dropped out of school the last month. I have closed myself off from everyone and everything i once loved. My life is ruined. I would go out and walk around in the middle of the night just thinking of the fastest way to end my own missouri. I couldnt find any no risk methods so i guess i just tried to swallow my pain. Eventually things got easier, well i just shut all my feelings inside of me and covered it up with alcohol, women and other substanses. I drifted away from my other best friend and im left alone in my own litte bubble drifting away while everyone else is going on with their own lives. I have been drinking heavily. The first party i went to after the incident i snapped. I blacked out and started fights with grown men and even the police, luckily they knew my situation and somehow let me go. I broke my hand that night wich led to me loosing my summer job. The only thing that could consume my energy for the summer was gone. I filled it with drinking hard and partying. I drank whenever i could and filled my emptiness with girls. As i am writing this I am fucked up on codeine and sleeping pills. So here i am, 17 years old, cant see a future for myself and pushing away everyone that is close to me. Is there anyone out there that knows what im going through, please help