Brew smaller batches. Every once in awhile I'll brew a 4-5 gallon batch, but mostly I brew 2.5-3.5 gallon batches. Around Thanksgiving and Christmas I ended up brewing 4x4-4.5 gallon batches in a row and I ran out of bottles and had to take a hiatus from brewing for 6-7 weeks, even with everything I plied on unsuspecting relatives over the holidays.
I've gone back to mostly 2.5-3.5 gallon batches now with the occasional 4-4.5 gallon batch.
Personally I can go through around 3 gallons of beer a month (I average around 1 beer a day). If my wife helps out, which isn't often, she can use up maybe .5-1 gallon of beer a month on average (she mostly drinks wine, but occasionally, either we are out of wine or she is "in the mood for a beer") as she normally only has 1 or 2 a week.
I/we also use it in cooking a lot. Depending on what I have in the bottle (I like to have a lot of varieties), it is great to use as a base for things like stews, crock pot dinners, battered things, cooking fish in it, pot pies, etc.
It isn't as cheap as water, but it is a lot cheaper than wine and I get a lot more varities a lot of times (nothing like using some stout/porter as the base for a nice shepard's pie or chicken pot pie).
Depending on what I am cooking in a month, I can use another half a gallon of beer a month cooking.
I also tend to give it away. I send my Dad home with a 6-pack everytime they visit and he brings me the empties. I don't see him as much as I'd like, but it is something. Sadly I swap beer with coworkers who also home brew, so I end up with their (excellent) beer instead of simply just giving mine away. I also ply it on my neighbors occasionally. My nieghbor helped plow out my driveway with her tractor over the weekend and I thrust a 6-pack on her in compensation.
If I had no kids or they were all grown up, I have NO idea what the heck I'd do (cook everything in beer? Beer on my cereal even?) as I LOVE to brew. Maybe it'll get old some day (I am only 20 months deep). I love to drink too, but if I am going to be self honest, I really don't think I can manage more than 10 beers a week and probably stay healthy (from a liver, addiction and waist line perspective).
As it stands, if I can I try to brew once a month, which gets back to the 2.5-3.5 gallon batches being close to perfect as it means I can generally brew every 4-5 weeks and slowly draw it down, throwing in the occasional 4-4.5 gallon batch and a couple of times a year I can "go crazy" and brew 2-4 times in a 1-2 week period (example, wife and kids are going away for spring break, but I have to stay home because I can't take off work. I have a minimum of 4 and possibly 5 brews planned for that week) and then take a 6-8 week break in brewing before I start up with small batches again.
that and for this summer I am planning on finally doing "light beers", like a 3.6% ABV Berliner wiess I am planning, a 5% Belgian Single and a 5.2% Dortmunder for that spring break brewathon. A 3.6 percenter I'd have no worries about knocking back a couple of those a night and 3-4 on a particularly hot and thirsty summer day. My more typical 6-7% ABV beers that I often brew are very much more just drink 1 a day, or occasionally 2 (3 if a really special occasion/party). So making 5-5.5 gallons of 3.6% ABV beer is a lot more doable than 5 gallons of a 6% beer as it'll take me a lot longer to drink the heavier beer (which means I get to brew sooner with the lighter beer, even though there is more volume than there is of what would be a lighter beer, which means I get to brew again sooner!!!)
One of the other things I want to start doing soon is stocking me cellar. I need to build up more bottles, but I want to start brewing RIS and Barley Wines soon and cellar aging them. Also sours. Since they take so stinking long to age properly, if I am brewing one of those every couple of months mixed in with my regular brewing (at least for awhile doing that) it shouldn't be a big deal. Sure it is extra beer, but it is going to take 6-12+ months before it is "ready" to drink and even when it is, I can keep drinking it for a year, or two or three (or more?). At some point I'd have to slow down, but if I put up a couple of different RIS, a couple of barley wines and a couple of sours in a year, I can cut it back to half that the next year and keep a good stock of the "special stuff".