Cleaning the house

I would like to know if anyone else has trouble keeping the house clean. I do, and its frustrating. I live with a cat and a dog, so it should be easy to keep my house clean. For me it's not. I get some of the house clean, do good at keeping it that way for a while, then something happens and it's a disaster again. Even the small chores like washing dishes seem huge. Does anyone have some advice on how I can overcome this. I know I will feel better about myself and less depressed once I can get this dealt with. I'm tired of having a messy house.