Hello Etak, and a warm welcome to the forums and sorry for the situation you are in, because if your husband has been a 'high functioning alcoholic for nearly 5 years', then even if he stopped, it would require a great deal of rebuilding the marriage, whether this is possible, it's too hard to even predict, as so much in this relationship would need to be changed on both sides and sometimes this may be possible, while other times, it may have gone too far and affected how you feel about him as well as the thoughts your children have regarding their father.
Being in this type of situation can carry a heavy burden on how to manage your family as if he has also become a cupboard drinker you might not be aware of, which will affect any financial issues for being able to maintain the family.
If he does decide to stop then he'll need help from those who are appropriately able to assist him, as an addiction for some people isn't easy to overcome, with the possibility of having a relapse, although that's unknown.
You are still entitled to proceed with the divorce even if he doesn't want to, as this happened to me when my wife wanted to divorce me, so if I didn't sign or object to it for any reason, it was still able to go ahead.
If I had refused to sign it and wanted to contest it, then it would have to go to court, which would involve lawyers, solicitors and the cost be expensive.
You have the option to sell the house, or alternatively, one of you can buy the other person's share and if neither of can come to an agreement, then it can be settled in court, so you can contact a lawyer on a no win no fee basis.
Talk to your doctor who may be able to help you with making a decision.
Ask any question you like.