Anyway, while I was tired, I thought of this trick: write down everything that comes to mind when you're exhausted, or depressed, or otherwise not at your best. Every subject matter that remains interesting at those times.
Then, when you're feeling better, go through that same list. Are those thoughts that are so native to you that you just fall into them easily? Do they represent you at your laziest? Or are they just very familiar and comforting to you?
Consider whether you want to keep those thoughts in your life.
But I haven't actually done this, because apparently that was one of those thoughts.