"There is nothing so easy but that it becomes difficult when you do it with reluctance" (Terence).
IT'S SAD THAT WE LET SO MANY GOOD DAYS BE RUINED BY THAT COMMON KILLJOY: RELUCTANCE. Activities that might be quite satisfying (indeed, activities that at one time were satisfying) are now seen, for one reason or another, as being required, and so we approach them unwillingly. With our resistance and reluctance, we drain every drop of joy out of our daily round of duties. It hardly ever occurs to us that the problem lies with our personal concept of duty.
We tend to draw a pretty hard line between obligation ("have to") and pleasure ("want to"). We think in terms of work ("have to") and play ("want to"), and we even divide life itself into two main segments: employment ("have to") and retirement ("want to"). We hack away at our "to do" lists as if happiness and delight were things that could only be enjoyed later. Yet there is no law in the universe that requires us to see "have to" and "want to" as opposites, and the mere fact that something is necessary doesn't mean we can't do it willingly. "The man who does something under orders is not unhappy; he is unhappy who does something against his will" (Seneca).
Many wonderful doors open to us when we learn the simple habit of willingness. We can consciously open our hearts and minds to the things that are ours to do, even those that are obligatory, and when we do, everything takes on a much better appearance. This doesn't mean we try to trick ourselves into thinking that everything we have to do is easy or pleasant. It just means we give these things the full assent of our will -- and also remember why we're doing them and who the folks are who benefit from them.
When we go to bed at night disagreeably "tired," the thing that has tired us out is usually not our work or our responsibilities -- it's running away from our work and our responsibilities! A reluctant, unwilling, I-don't-want-to-do-this mindset is one of the most exhausting things that anybody can endure. So get rid of it. Make a different choice. Embrace the things that you must do, and you'll find an energy surging up inside you that you'll have great fun putting to good use.
"A willing mind makes a light foot" (Thomas Fuller).