Bump on a Log

I have not been cleaning very much lately. With the help of my significant other, we manage to keep the house looking about 75% clean most of the time. The dishes mostly get done, and things aren't laying around, but we could certainly mop much more often and change our bed sheets. We planned so many things, now we just say we we will each clean for two hours on Saturday and that worked really well for one weekend but the next weekend we had an emergency and things fell by the wayside. I know there are many others out there who lead extremely busy lives and still manage to clean regularly, so how do you do it? How do you stay on top of things even when a family member is sick or you are going through a stressful period at work, etc.