We often trick ourselves with this whole "functioning alcoholic" thing. Yeah, we can go to work and pay some bills and have fun and stuff, but we aren't living our lives the way we know that we could and should. We don't have to be jobless and destitute and living under a bridge in order for alcohol to be having a negative effect on our lives.
When my car needs an oil change, it's still "functioning," but not running at its highest level. And if I don't get that oil changed in a timely manner, the car will stop "functioning" and will end up in a state of disrepair, and it may even be damaged beyond repair. Best to handle those issues before they ruin everything.
If your whole life revolves around drinking, and if it feels like your life is a prison, that's no way to live. Sure, you can function inside a prison (I did it in jail...only for 3 days, but I survived). But the question before you now is: Do you want to live a life where you merely function, or do you want to really live life on your own terms?