this hurts me worse than it does you

This hurts me worse than it does you is usually said from a parent or guardian to their child after punishing them. What the phrase means is that while the punishment is hurting them (even just emotionally) it is hurting them too because they hate to punish their child, but sometimes it has to be done. It is a way to say that the punishment is for their own good, not because they enjoy doing it.