Mary Maclane said this quote

If you ever feel to express proper gratitude for the good things of this life, be sure that you express your gratitude for the right thing. Very likely you will not have a great deal of gratitude, and you must not waste any of it but what you do have will be of the most excellent quality. For it will accumulate, and the accumulation will all go to quality. And the things for which you are to be grateful are the bitternesses you have known.If you have had it in mind ever to give way to bursts of gratitude for this air that comes from off the salt sea, for that line of pearls and violets that you see just above the horizon, for the health of your body, for the sleep that comes to you at the close of the day, for any of those things, then get rid of the idea at once. Those things are quite well, but they are not really given to you. They are merely placed where any one can reach them with little effort. The kind fates don't care whether you get them or not. Their responsibility ends when they leave them