Motivation?

Sometimes it gets difficult for me to muster the energy to do the right thing, especially when in comes to nourishing myself. There are always days when I don't have the energy to prepare a full meal, or even to go food shopping. So how do I find the motivation to get myself nourished, even when I'm not feeling up to the challenge?
Usually it takes me a while. I'm not the best at motivating myself. In fact, I'm much better at motivating other people. Sometimes when I get home I'm tired and can't find the strength to eat. I usually lay down and take a nap. But it is self defeating because I just wake up later, even hungrier than before. So what is it that I can do to change my mind and get myself where I need to be?
Sometimes just plugging in the stereo and getting some good songs on the radio is the only way for me to drag myself into the kitchen. The other thing that motivates me is the knowledge of what didn't work before. It helps to think back about every other time that I've talked myself out of nourishing myself...only to have to step up later and do even more work to repair myself.