To draw an analogy: a man's suffering is similar to the behavior of a gas. If a certain quantity of gas is pumped into an empty chamber, it will fill the chamber completely and evenly, no matter how big the chamber. Thus suffering completely fills the human soul and conscious mind, no matter whether the suffering is great or little. Therefore the "size" of human suffering is absolutely relative.
Viktor E. Frankl (2015). “Man's Search For Meaning, Gift Edition”, p.40, Beacon Press