I was a functional alcoholic for the past 8.5 years - though "functioning" meant forcing myself out of bed to go to work and being miserably tired and defeated all the time. There's a difference between functioning your way through life and living it with freedom, spirit and joy. These things were not possible when I was drinking (on Day 64 now).
What's more, one day this past January my "functioning" snapped when some high pressure things and stress came together in a perfect storm. I basically said "f&*ck it", and slid into oblivion of a three day binge that landed me in the emergency room. I lost my job. This has been my pattern before in life, I have not had the progressive stages like others describe. More, it's been hanging on by my fingernails by doing what I need to function through life, job, etc. - then falling from the branch and hitting the ground hard.
Whatever your situation, I would agree with others that quit before really bad things happen and be thankful you took the step when you did. Others have lost jobs, gotten DUIs, split from their significant others, and other worse things we never saw coming. Good luck and keep coming back.