I don't keep a record of names or have a head count of numbers of people who are BPD and drink, but I do know that there are others here who deal with the same things you are dealing with. If you look about on the other boards, I am sure you will find much info and help for the drinking. May even find another there who has info for dealing with other issues as well.
Going where the help is at sure is faster then waiting for them to come to you. Are you on meds for the BPD? If so do you share with your Dr that you drink? Alcohol can reduce the good effects that meds can bring.
Another reason to maybe stop.