I suffer from severe depression and panic disorder to the point that I am on disability. So, I know how awful depression can be. I can empathize with the feeling of having a gaping hole or feelings of emptiness. I can also tell you that drinking alcohol only exacerbates those feelings. I found when I was sober, my panic attacks disappeared and my depression got much better. I remember thinking, "wow, sobriety feels much better than I thought it would."
If you are afraid you will have mood swings and become violent, I would let the detox center know about BPD diagnosis so they can be prepared if you become violent. I do believe they provide benzodiazepines when detox is difficult as to prevent seizures.