Divide and Conquer
Divide each difficulty into as many parts as is feasible and necessary to resolve it. - Descartes
I separate myself into areas of interest. This way I can decide if something I am doing is worthwhile based on whether it benefits some part of me that I would like to see improved. There's exercise, education, work, stress-relief, etc. There's nutrition and cooking which are their own things. In this way it's easy to think of myself as a mechanism like a car or computer. The car has an engine and within the engine are many different parts. As you replace or perfect one the entire mechanism begins to function better. This alludes to some kind of perfection which can be reached where you will be a faster, sexier, smarter, higher performing car than any other. What will you do then? Will you find endless happiness? Of course not, because you are not a car. You are (more like) the mechanic. A problem solver. The joy is in the aim to improve, not in the improvement itself. It's getting your hands dirty trying to figure out how this life-thing works, piece by piece, exploring it.