As I have learned the hard way....highly functioning really only applies to people that aren’t close to the alcoholic as they are able to keep up appearances for others. I realized that my XRAH was highly functioning away from home but at home he really was not very functional at all, drinking a sleeping and very much unavailable emotionally. Which is why I could not recover from his years of drinking when he finally got sober. Too much damage to the person closest to him while no one else had a clue he was an alcoholic. Any alcoholic parent whether functional or not is unhealthy because they cannot have a normal healthy relationship with those closest to them because emotionally they are very much absent. Of course your AH will not understand that as long as he is an active drinker. Sorry no resources but that’s what I learned through family program at rehab and through counseling.