Hi cerid, glad you decided to post. For context, I also had an alcoholic Father.
Can a person grow up in a household with alcoholism and not be affected? I'm sure there are some who can, or who realize the affect and take care of that early on.
Doesn't sound like that is the case for you though? I'm going to guess your Mother's treatment of you in relation to that probably had far more impact that your Father's alcoholism did though.
As for not having him live longer and being able to be angry at him and at alcoholism etc - well every experience if different but I don't know that it really helps. Far better to get to the root causes of any struggles you are having now than looking back.
As for your current relationship. In childhood we learn how to treat people and how to be treated. You mention that you resent your Mother not having more compassion for your Dad. That kind of suggests that maybe, just maybe, you are playing that out right now.
Does he treat you well? Does he disappear for days? Can he be moody and erratic? Your current relationship is in fact a recipe for disaster. Alcoholism is progressive. Him "working with a doctor" sounds like just putting it off. Until he actually quits using any drugs and gets totally sober and goes through recovery, you don't really know him.
You know him as an alcoholic, he may be quite different when sober. Even if he goes a day or two without alcohol, that's not the same as being really sober and in recovery.
You might also want to check out the Friends and Family of Alcoholics forum:
https://www.soberrecovery.com/forums...ly-alcoholics/