Basically, Curtis had chosen to wage an open war against the Rothschilds because he didn't want his family to suffer, while also anticipating that they would disown him after making enemies against such a terrible entity.

It's like person A knowing one's lover would cheat, but willingly allowing them the chance to do it and leave person A so that the lover wouldn't have to stay out of obligation.

Even in death, Curtis still cared for his own family—for his father, who didn't care what happened