Hi Incognito,
It is definitely possible to have "functional" alcoholic SO. You list a lot of things that are wonderful about your boyfriend, which I'm sure are true. However, the fact is that his drinking is a problem for you, which means it is a problem for the relationship. One thing that is very difficult for a "functional" alcoholic to understand is that alcohol can be a problem even if it isn't causing you to lose your job or be abusive.
One of the things that you mentioned in you other thread is that you don't want your kids to grow up with the example of seeing someone with a beer in his hand all night every night. Only you can control whether that is what your kids see, and by choosing to be with this man, you are exposing them to daily alcohol. I don't mean that in a mean, harsh or judgmental way, so please don't be offended. But do consider that while you have the freedom to choose who you are with, your children do not have that choice, and you must always protect them.
Another thing that you mentioned is that you are afraid that your SO will change if he stops drinking. That may very well be true, especially considering that you really never see him sober.
My husband is a highly functional alcoholic who does not think his drinking is a problem. It caused me great stress, not because he is "falling down drunk," but because I do not believe he can or will control his drinking, and I believe it will only get worse unless he decides to get help. I feel that I have the right to spend time with my husband in his natural state of mind, but he does not agree. If I had known that he was going to turn out to be an alcoholic, I would not have married him. I would urge you to carefully consider whether you want this problem in your life permanently. And it will be in your life permanently because you cannot control whether your SO drinks, and even if he gets sober, you have no way of knowing whether it is a permanent change.
I'm so glad that you are thinking carefully about your situation, and that you are looking for help and information. Alcoholism is an overwhelming problem, and I truly appreciate your situation. I hope that everything turns out well for you and your family, and I'm glad you are here.
Sasha