Is his brain changing that fast?

You say in your profile that he has had multiple tests, including an MRI. What does the neurologist say?

My first thought is stroke or continual small TIAs leading to sensory deficit or sensory inattention; but please note I may only think that because this happened with my mother - it's all too easy for a layman like me to think "snap!" when in fact there could be something completely different going on. Does your husband have any diagnosed health conditions at all?

Dementia-guide-dot-com is a great resource. If you check under the "learn" tab they have a symptom library.
"Although loss of initiative sometimes is present before the diagnosis of Alzheimer’s disease, it generally occurs in early dementia and becomes worse as the disease progresses."

Has he been diagnosed with something?