I do the same thing even though I know how to cut it down. When I was 18 I worked on a dude ranch where all the meals were cooked and served family style. That's where I learned the "cooking for an army" mentality and I haven't been able to shake it since. I think it's partly the pleasure of stirring, chopping, sauteing, that leads me to make such big batches. So I just put the extra in freezer bags for later use or better yet, give it away.
"First we eat, then we do everything else." M.F.K. Fisher