Rehab

I really can't answer your question without more information. What are using? How much? Have you tried to stop using? Have you tried Narcotics Anonymous or Alcoholics Anonymous meetings? I would say your best chance of recovery is going to rehab. The longer, more intensive treatment generally has the best chance of success. If you have never been to rehab before, then I would definitely suggest it. Without rehab, you probably know nothing  about how addiction works, what it does to you or how you can get better. People usually learn about addiction by going to rehab, recovery houses and NA meetings. You need this knowledge to get better. 

I hope this helps and you can find the answers you are looking for. Good luck with your recovery!