When my AH quit drinking, it wasn't long till he started the behavior you are seeing.
"Several days a week, he comes home and sleeps and avoids even speaking to us until the next morning when he leaves for work."
I found out he had simply switched his addiction from alcohol to xanax. It works on the brain in the same way as alcohol, but there was no odor, and no hangover.
I knew it was not normal to be able to sleep that many hours, but it took a while before the reason was disclosed- xanax addiction.