Help me! I am a emotional roller coaster!!?

I have a drug addiction and I feel lost. I am not only hurting myself, but everyone around me. I feel so hopeless and worthless!! Please tell me what I need to do to get back up. I am tired of being up-side down. I thought I had thie thang beat, but right now it's kicking my a@%... Nothing seems to be working. I feel like I want to stop, but it keeps calling me!! I find myself using more than i ever have in life. I feel so depressed and often suicidal. No one trusts me or believe in me anymore. I don't blame them because I have let everyone down, especially myself. I've tried everything. Meetings, positive people, counseling, you name it and the drugs still keep finding me. What's really wrong with me? Am I just insane or what? I don't even know how to describe it!! I say I am tired, but obviously not tired enough! Please help me! I've fallen and cant seem to get up for nothing in this world. I am good at giving advice, but poor at taking my own. I need suggestions!