Hi Jay.
Lots of folks don't seem to know why they post here at first, but most report concerns about their drinking. Few people who don't have problems with alcohol can quote the when, where, how, how much and how often of their drinking.
I coordinated a large-scale, multi-site study on the genetics of alcoholism and, regardless of individual experience, both depression and alcohol problems carry a genetic component and therefore "run in families." What this means, among much else, is that we cannot control either problem on our own, and that we cannot turn back the clock once these difficulties emerge. They are essentially hard-wired and are generally triggered by environmental stress.
As Dee commented, your "domestic arrangements" are complicated and likely carry levels of co-dependency that both sustain and nurture the problem. Very often, we cannot see how our living arrangements are hurting us (and others) and are, in fact, making things worse unless and until we change things around in that regard. I can't speak to your desire to cut down on/control/moderate your drinking, in part because I've never tried to do so, but also because I've never known anyone who's been successful at it over the long term. Most times, it only prolongs the problem and often makes things worse.
The good news is that you have a lot of options here, before you descend lower into the rabbit hole you mentioned. Go to a couple of AA meetings and hear what others who struggle with alcohol have to say; make an appointment for a screening for outpatient treatment in order to get a professional perspective of where you're at (there's no requirement to enter treatment based on an intake interview alone), read up on AVRT here and across the Internet and, as others have suggested, do some research on what entitlements (which is what we call government-based benefits in the States) your mother may be eligible for -- essentially using what seems like a part of your co-dependency in a healthy way. Sticking around here has helped I don't know how many thousands of people to sort things out and take appropriate actions.
It's a great thing that you came here before everything has spun out of control; the thing is to do something about it before it does.