This is one of the easiest posts that I have ever had the pleasure of responding to.
Your husband is a selfish human being. If he lived by himself and wanted to be depressed and anxious I say it is stupid but it is his choice.
Since he has been married for 47 years and refuses to get treatment for his depression just makes him stupid and narcissistic.
Give him an either or ultimatum. Either he gets help or he gets out of the house. You are a cancer survivor and you don’t have to spend the remainder of your life living with an idiot. You don’t mention children but if the two of you have any along with grandchildren just enjoy them and let him wallow in his depressive state.
It is really probably too late and costly to get a divorce. If you have a second bedroom move in and just pretend he is not there. You don’t deserve to have to live like this.
Your husband is an idiot who doesn’t like the side effects from treating his depression. Anyone with depression who is this selfish deserves to be miserable everyday of his life. Just don’t let him take you with him.
Good luck to you.