Detachment is one of the very BEST things we can do.
Having a front row seat to your dad's addiction has not been healthy for you.
You have your own path in life. One that can be free of being a codependent in his life.
You are powerless over him and his addiction.
Only when he gets sick and tired of alcoholism, will he change.
Set your boundaries w/ him. Tell him you love him but that you can't talk when he calls if the conversation is not a healthy one for you.
Don't feel guilty for doing what you need to do for yourself. it is also good for him to know that you support him when he wants to get sober but not in his sickness..
You sound like you are making great progress in your own life. Way to Go !!!!!!!!!!