My brother in law is a crack addict. Anytime he has relapsed, it began with drinking a few beers once in awhile, and eventually, back to the hard stuff, and an arrest. The arrests and jail time have saved his life at least 3 times. Forced him to get clean. Two were rehab type facilities.
That is just my only experience with knowing how strong a crack addiction(and alcohol) addiction can be.
8 years is fantastic! Why ruin it? Why take a chance on it?