Wow, Chad, you've just given me a trip down memory lane to how things were between my girlfriend and I when we first met 11 or 12 years ago... I know exactly how bewildering and shocking the outbursts are - the whole "Where did that come from??!?" thing as the evening turns from being fun to suddenly being one where you're pinned to the wall by a torrent of abuse. And then the morning remorse and yet, and yet... she'll still do it all over again.
Are you at the stage yet where you start to feel tense before a night out with her at a friend's house? You know she's likely going to drink too much, but you're walking on eggshells around her and not mentioning it in case doing so annoys her and that's the reason she drinks too much...? You will.
Here's how it seems to me. She knows she's got a drink problem. She knows that she behaves badly and causes offence to her friends when she's drunk. She also knows that she treats you badly - the man she presumably professes to love - when she drinks too much. And yet... she's happy to continue drinking. Whether she's an alcoholic right now is impossible to say and, to be honest, beside the point. That's her business. Whether it will get better or worse is, again, impossible to say. All I can say is that over the years my girlfriend's drinking got worse and worse, the abusive episodes got more frequent and nastier, and eventually we split up and our kids live full-time with me as she's just too much of an unreliable drunk. Last I heard is that she's in rehab.
But let's turn the perspective from what's up with her to what's up with you. You're in a relationship with a girl who will, on occasion, treat you appallingly. She blames the effects of alcohol for this, but she continues to drink. In effect, then, she's saying that she's more willing to continue to risk offending you and hurting your feelings by being awful to you than to do something about her self-confessed drinking problem. Actions most definitely speak louder than words in these situations and that is what her actions are saying. Is this the kind of relationship you want?
I'd recommend going to a few Al-Anon meetings to see if they're appropriate for you. Being in a relationship with someone with this kind of Jekyll and Hyde personality is really hard work and can seriously dent your self-esteem. Or, some counselling may help you to identify what it is that you really want from your life and aid you in setting boundaries for what you consider acceptable behaviour from others, and what to do when those boundaries are transgressed.
You can't do anything about her drinking; nobody can force someone to stop drinking too much if they don't want to. She'll either continue to drink or stop drinking entirely for her own reasons and at entirely her own pace. That's her business. Your business is if you want to be around that or not.
Take care,
Mr B.