You seem to forget who visited her in prison. Getting her to the end of herself may well have been somewhat a matter of chance. She was ready to surrender.
But that is NOT how Angel saves her. He saves her by visiting her and being there for her.
I will only say this once more. Her horrible behavior *is* horrible. It is also largely a symptom, not a sign of lack of good character. We largely see that character when she comes back to Sunnydale in season 7. (That she keeps fighting while living in that hovel in season 3 and goes to the the vampire church and helps kill vampires in 4 also shows some character)
What we see most often in season 3 is a broken, feral person acting out. This is never fun to be around.
Faith is, writ large, why MOST abused and damaged people don't get helped. Abused children are not pleasant or polite. They CANNOT articulate their pain, so they are hateful.
They are screaming, kicking and biting for help. All that is obvious is the screaming, kicking and biting!
Those who could help get caught up in their power.
Family and friends get JUSTIFIABLY hurt and angry. I never say that Buffy, Xander or Willow fail her. They don't. They simply do not have the tools to help her.
I am not putting Angel on a pedestal. A lot of the time I find him insufferably pompous and broody.
But. He did what she needed. He was strong enough when she was flailing blindly and unlike Buffy (understandably) he was not emotionally involved.
Unlike the council, however, he saw a person, not a problem to be exterminated.
Please try to see the nuance in my argument and not get defensive for Buffy and co. They *could* not help because they did not "get" her and because they were CHILDREN.
The people i condemn here are the council and to a lesser degree, Giles and Wes - who is barely able to function because he is not ready. Mostly, I blame the WC for him too.