If I were diagnosed with Alzheimer's, I would seek out assisted suicide. But I think it's more complicated than that: its existence incentivizes pushing people toward assisted suicide. The government finds a way to help with bloated medical care budgets; unscrupulous family members guilt trip the sick to choose the option to keep the inheritance intact.

The best solution allows it for severe cases, while still investing money in research and spending money for palliative care so it remains an option and not a demand. But that's a tricky line to maintain.