OSWALD. [After a while, looks up and remains resting upon his elbow.] If it had only been something inherited – something one wasn't responsible for! But this! To have thrown away so shamefully, thoughtlessly, recklessly, one's own happiness, one's own health, everything in the world – one's future, one's very life – (2.280)
Almost more than the illness, Oswald is tortured by guilt and regret, believing as he does that he brought it on himself. While he defends the artist's way of life, he believes he is too weak to take part in it.