No such thing as "quitting gradually." That is still using, just a bit less, and using, even a bit less, leads back to using about as much as before. This is called an "addiction" for a reason. No one can continue to use, and get clean. So, the reboot has to be going totally clean. That sucks by the way, totally sucks. For me it felt like dying. But, I told myself, if quitting the addiction results in me dying, I am dying. It won't kill you, though. Promise.