I love this! What a completely original configuration of people and yet so believable. You Millicent is rough and unsubtle and she has the kind of living-with-reality that enables people to survive - just the person to take in a slim reed like Dennis. Great job.
YOu have one teeny misspelling - "horded it away for future use," should be "hoard."
This reminds me of a book I think you would like, Tell Me That You Love Me, Junie Moon, by Marjorie Kellog.