¿Cuál es la diferencia entre abject y bitch-ass y stupid-ass ?Puedes dar oraciones como ejemplo.

"Abject" means to be in an extreme low state. You will see it in set phrases like "abject coward" "abject poverty" and "abject misery". "Abject" can also be used to mean a person who is abasing themselves, though this usage is less common. In general, "abject" is a word that may show up in daily speech, writing or more formal speech, like a politician's speeches, novels, talking with parents, etc. "Abject coward" could maybe be used to insult someone directly, but it is unlikely to be used in the middle of a heated argument, although it might be used before or after.

"Bitch-ass" and "stupid-ass" are very informal. They can be used to playfully insult very close friends. They can also be used in heated arguments. They can act as expletives when a person is angry. "Stupid-ass" would be used when implying someone or something is dumb or an idiot. It is the less aggressive of the two in "standard" US English, because "ass" is a weaker curse than "bitch." "Bitch -Ass"
implies weakness, but not necessarily stupidity. "Bitch-Ass" African American vernacular, and only became used by other groups in the last few decades, so it's usage is not universal in older people. It would be just another swear to younger people, though.