It is maddening, to see two sides of a person and know that the chemical is always present when the bad stuff comes out.
I wrestled for a while to know if the truth was what came out when the alcohol was in the system, and the falsehood was when she was sober, but there really isn't a clear answer to this, and it usually is a mixture of both. Since alcohol breaks down inhibitions, things are done and said that may never have been said sober, but just because they are said, doesn't mean they were intended or even meant or felt. It is just the alcohol breaking down a barrier that most of us never even consider exposing.
All that said, the bottom line is how her behavior affects you and makes you feel, and making sure she is aware of that. If she continues this behavior knowing the negative ways it is hurting and affecting you, you have to make a choice on what YOU want for yourself and your life.
It's a tough spot man, I've been there. Keep posting and we will help.