Image Courtesy Mi Pah
From Merriam Webster:
Main Entry: wea·ry
Date: before 12th century [People have been feeling this way a long time!]
1 : exhausted in strength, endurance, vigor, or freshness
2 : expressing or characteristic of weariness
3 : having one's patience, tolerance, or pleasure exhausted —
wea·ri·ly \ˈwir-ə-lē\ adverb
— wea·ri·ness \ˈwir-ē-nəs\ noun
Weariness takes the pep out of our step. While feeling weary can be caused by many things, and can vary in length from a few days to several months, the end result is the same: we feel like doing little more than the bare minimum--and sometimes even the bare minimum is tough. The nature of motherhood alone--despite all its joys--easily fits definition number three of weary, "having one's patience, tolerance, or pleasure exhausted." Once your "patience, tolerance, or pleasure" is exhausted, you'll have little "strength, endurance, vigor, or freshness" (definition number 1) to give to anything else--especially housework.
Realizing that weariness works against us when it comes to getting housework done regularly and well is helpful. It's helpful because, once you understand what the problem really is, you can begin to form some realistic solutions. There are definite seasons where weariness (and thus, low productivity) are quite natural: sickness, the birth of a child, a death in the family, a major life or job transition. In these seasons, cut yourself some slack. (In all honesty, I am just now starting to feel more consistently energetic--and I had my baby 16 months ago...but I also have three under five who just about exhaust my patient and tolerance every day--good thing we get a new dose daily!).
In wearisome seasons, identity your bare minimum housework goals and aim to reach those--and really only those--each day. At least you'll feel successful for having done that. They will be different for every person, but for the sake of an example, let's say they are: having a clean sink at the end of the day, sweeping the kitchen floor, and wiping the kids' boogers off the walls (for a little humor). :) I encourage you to talk to your husband and figure out what his basics are--if everything else is undone, what few things does he need to be sure are done to be happy? Go from there.