I agree with a previous suggestion, whether she believes you or not. Say you are on the wagon for a period and want no temptation. She then has a choice........
I dropped a good friend, pals over 30 years, because he was "pre-loading" before arriving at my house, worse, the "pre-loading" was taking place as he drove, he too would be a ga-ga spent force early in the evening, it was predictable, boring and having an adverse affect on my children.
I don't believe calling alcoholism a disease (don't believe it is one anyway) helps either, that only produces a stigma, no wonder some can't or won't confront or accept their problem. The OP is contributing to her problem, maybe she could see one if she was left to miserably drink alone, but if others are giving and participating in her problem hey! Where's the problem?