Damn.
Crap.
Merde.
*Otherexpletiveindicatingfrustration*
Ok, well, if this pregnancy is for real, if she doesn't miscarry (it happens more than you know), and if you are the biological father, this is a whole new ballgame memphis.
The statement "At least I know I wouldn't drink for 9 months" is total bull. Despite all the goodwill in the world, she is ADDICTED to a substance and it'll take a monumental effort on her part to keep herself from drinking. I strongly suggest that you discuss with her doctor her drinking as well as the implications of detoxing while pregnant (if I remember correctly, she's constantly drinking these days, right?). I don't know what the ramifications would be for the fetus.
Normally, I'd just say "step away from the alkie" but in this case, you may well be dealing with your unborn child who has no protection whatsoever against his or her own mother's addiction. As much as it sucks, you may have to intervene to protect your child, but then again, you can only do so much.
Please let us know how things went at the doctor, but more importantly, please let us know how YOU are doing.