I'd have to say I became a responsible mature adult through a spiritual experience and growth subsequent to getting sober, not before.
As a drinker I was anything but mature and responsible. My emotional age was round 13, my medical psychiatric reports talk about someone who is childish, grandiose, opinionated, dishonest, a greedy self lover, self centred, irresponsible and selfish. Hardly the character of a mature adult. And the literature I have seen on the subject often seems to describe chronic hopeless alcoholics in the same general way.
The result of sobering up was the opportunity to develop into a mature responsible adult. The alternative would not have allowed me any of those things. I was only a few months away from the end when I stopped.