Sorry you are going through this, Jen.
My thoughts?
Given his age, he could very well be showing early signs of some type of dementia, superimposed on his alcoholic brain. But, I'm not a Dr. and can't diagnose so take what I share that's helpful and toss what you need to toss.
He's been diagnosed with depression, right? It could be worsening depression and a very deep depression. With depression, you can see loss of appetite, loss of interest, "blah" moods and facial expressions even with things they used to enjoy a lot. They interact less with others, they tend to isolate. And, yes, they also turn to substances such as alcohol to self medicate. I've been through that myself. But, when I was going through it I was very fortunate to have a Dr. who really listened and was open to trying different things, different meds, etc. Just from my PERSONAL experience, the best anti-D I ever took was Cymbalta. It's a little on the expensive side and not all insurances will pay for it, so there you go....I took myself off Cymbalta very gradually after being on it for awhile and still experienced quite a WITHDRAWAL. I hate to make it seem like meds are the only answer, but they do help a person get through the worst of it until they are up to making other changes in their life like eating better and exercise.
Diet and exercise and good sleep to me are so ESSENTIAL for mental well being and have a great impact on depression. Unfortunately, alcohol just makes depression worse, that's is a lose-lose option to deal with depression, but a lot of alcoholics are depressed.
I don't recall if you said he had a counselor. I hope so and also hope it's one that will be helpful. The underlying issues need to be dealt with...but again, sometimes a severely depressed person isn't up to ANYTHING including getting out to appts.
Not caring about hygiene and wanting to wear the same clothes over and over sort of reminds of my senile grandmother that lived with us for awhile, but it can also be part of other mental illnesses and very common with depression. It's like they lose all interest including interest in personal care. It's debilitating, really and yes, it's very hard on the family.
Dr. and nurses really NEED to listen to family members who live with this because it's when you really LIVE with something that you grow to know it the most intimately. Here's hoping you all will have brighter days ahead.