A quote
“But it is a hardship,” men say, “to do without our customary pleasures,—to fast, to feel thirst and hunger.” These are indeed serious when one first abstains from them. Later the desire dies down, because the appetites themselves which lead to desire are wearied and forsake us; then the stomach becomes petulant, then the food which we craved before becomes hateful. Our very wants die away. But there is no bitterness in doing without that which you have ceased to desire.
Seneca·Letter 78 — On the Healing Power of the Mind (§11)·trans. Gummere