It is the lies he's telling her - as he has been, Nassun understands suddenly, her whole life - that really break her heart. He's said that he loves her, after all, but that obviously isn't true. He cannot love an orogene, and that is what she is. He cannot be an orogene's father, and that is why he constantly demands she be something other than what she is.
~ N.k. Jemisin