No one can possibly offer the "right" answer, since there isn't a single one that is one-size fits all. That said: a persistent onset of symptoms/behaviors may offer insight into what decision is the best in your situation.
Fading and out? That's different from persistently not knowing -- such as not knowing from one day to the next compared to a total lapse in recall or recognition.
If a cause for concern, I'd acton the notion of not wanting any regrets in life. Just my take

And, I wish you and your family the best

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".... This world wasn't built for people in wheelchairs ...."
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