Not Enough Pain
I’m not sure this is a good idea, but since it sounds like you’re doing your best to mitigate the consequences and doing your best to persuade her, perhaps you might consider letting it go for a bit until there’s an eruption. (I’m assuming the eruptions are unpleasant but that no one is in physical danger.)
Then perhaps in the wake of an eruption she might agree to the measures that will help her.
Kudos to you as it sounds like you’re trying all the things you should do but most people won’t change until there’s enough pain to cause them to do something different.