relapsed onto what? some drugs it honestly doesn't even matter; alcohol is by far one of the most dangerous drugs even drinking it in moderate quantities. I take adderall for add and klonopin for anxiety (although i take that not nearly as much now) and it doesn't mess me up anymore than 3 beers in a night or 2 cups of coffee in the morning would. even stuff like painkillers aren't really bad for you unless you get super addicted in which case the danger of overdose or problems from snorting, smoking or shooting are the negative consequences.
don't try to quit everything at once or you'll relapse and fail, take small steps and ween off things and go for short proximal goals and you'll be better off.