Welcome, dancer. By the way, "do my best..." is addict speak. It is like you're asking for our forgiveness for your short-comings in advance. Well, I personally don't give a shit if you half-ass it, give 110% or whatever as long as you stay quit.
That is your commitment when you come here. There is no "did my best" about it. YOU CAN DO THIS!!! That is all there is to it. You quit, give your word, and that's that.