First, I am sorry for everyone's loss.
Second, I can relate. In 2001, my GF was killed in a violent car accident. It was very tragic, and she had children who were also injured. The family basically shunned me (long story).
What I can offer is this: Get Help. Seek a grief counselor, a therapist...get into treatment for your addiction. This is a pivotal moment in your life...this your chance to fix things. He is gone...you need to move on, and live your life in a healthy way. I know, a little harsh...but I almost died after my gf died, and I don't want to see anyone take that path.