sister is a alcoholic

my sister is a very bad alcoholc and drinks strait vodka everyday. she passes out and sleeps all day, cant keep a job, doesnt eat anymore and everyday i see her she has even more red bloody sores like bites all over her body where she is bleeding thru her shirts, all over. my dad took her to the doctor and has an appointment on monday but she doesnt want to quit, and we cant, my family and i, watch see her kill herself. her stomach is extended and her face is blotted, but all these bloody sores are from what? though maybe bedbugs, or fleas but sprayed and fumigated and she just keeps on getting worse. she can keep a job anymore and thinks she gets fired for someine else mess up. i dont know what to do or what to expect when she goes for her appointmen but would like some heads up about it.... please help!