In Sal’s mind, Momma can do no wrong. So even if Sal might resent Momma for leaving on some level, she’s trying to come up with any reason to shift the blame onto someone else. The answer, she decides, is to try to blame Dad, which is part of the reason why she’s so closed off from him. But because Dad is so kind, this is difficult for Sal—and by wishing Dad was meaner, she echoes Momma’s own resentment of Dad’s goodness.