I guess what I'm asking is if anyone's been in a similar situation and what I should do about it, and how to go about doing that (like telling her I love her no matter what, but I can't be around her while she's drinking).
That's exactly what you should tell her. She know what is what. The last thing you want to do is put your own sobriety at risk, so yes, you do have to be selfish. Telling her you love her but can't be around her while she is drinking is honest. Honesty is always best. She will probably understand since she has been in AA and sponsored others. If she doesn't, well, there's not much you can do about that. Take care of yourself. She knows what to do if she truly wants to get back into recovery.