One thing I've learned in my recovery is that nothing is black and white. Always is one of those things one can never say with certainty, because there are exceptions to every rule.
I would say it usually gets worse, but how long that takes can vary greatly. And, it's not always the amount of alcohol that is progressive, but the effects on the alcoholic. Not just physical effects, but also emotional distance, enthusiasm, lust for life, etc.
So, out of curiosity, why are you here? It sounds like you and your H are content with things the way they are?
L