And if she says something like “well old people did contribute so much in the past”, just say that so did depressed people and often they are depressed because of giving more than they had.

Or maybe agree with her and drive it to the ultimate conclusion: people with disabilities will need to be euthanized if they can’t contribute. Working accident and you lost a limb or two? Euthanization.

Remind her to update her living will to let her die in case of an accident causing severe disabilities.