You probably already know this, but alcoholism is a progressive disease. It will get worse. "Under the Influence" by Milam and Ketcham is a really good look into the progressive nature of the disease and what you can expect in the future when living with an active A.
My AH was a closet drinker too. Once I put it all together, I was shocked by how easily he was lying to me (and everyone else, and himself). I too had lived "numb" for a number of years, but I have finally filed for divorce. The kids and I have also moved out.
I have an 8, 4, and 2 year old. I explained to my 8 year old that alcoholism is a disease, a progressive disease that affects the brain. Your dad makes bad decisions because of it. Those bad decisions can harm our family in a big way, so I have decided that it's best that for us live apart from him. I also talked about Al-Anon's 3 C's.
If they have questions, I answer them honestly and in a way they can understand, and then we get on with the business of living a life as lovely as we can make it. From what I have read, alcoholism often passes down through the family when there is an effort to ignore or cover it up. A lot of damage can be done when ask our kids to ignore or cover up a parent's alcoholism. My 8 year old son loves facts, so I did get him one book from the library about alcoholism. He read as much as he wanted to and then we returned it. Knowing the physiological facts of alcoholism helped me tremendously, and I think it helps my children too. When my AH was in rehab my 4 year old told our neighbors (middle class professionals--much like your neighbors, I gather) that his dad was in the hospital because he drank too much alcohol. And frankly, that was a perfectly fine thing with me. Those are the facts. There is no escaping them. It's a nasty, debilitating disease that can and most often will take down the strongest, kindest, funniest, most loveable person you thought you'd ever know.
Divorce was a hard decision (even after my AH started punching holes in the wall) but I think asking myself the following helped me too--How often do I have a big belly laugh with my kids, or dance around to music in the kitchen with them? Those were things I found myself doing when I made up my mind to leave. When I had the mindset of "just give it another few months" I was short-tempered, grumpy, and far from being able to be silly and fun with them.
I guess what I'm trying to say is that I knew that they need a capable mom, but I also came to realize that they need a happy mom just as much. They need to know that all the hard work they do in school and towards becoming responsible adults means that then they get to be happy adults who can laugh at a goofy pun or belly flop onto the bed with them, adults who take pleasure in good food, long runs, skiing, camping, gardening, reading, etc. Adults who make good decisions and follow through on them, in an attempt to live a peaceful and joyful life. There is so much more to life than working and passing out on the couch (or trying to cobble a life together with someone who does).
I hope this doesn't come across as giving advice, I just wanted to share where I am, as we are in similar situations.
And more importantly, I hope you are able to shake that numb feeling and start taking care of you. You deserve it!