I am not in AA, BUT if your boyfriend is going to continue to drink and you have no apparent support nearby then I would highly suggest you look into a meeting of some sort. There's Smart Recovery too, but you wondered what you would do during the witching hour and this might be an answer. It also would give you people to call so that you don't take that first drink that leads to the next and the next.
I can't help you on the rash, but I look forward to hearing how you make out with your doctor. Very important to see the doctor.