"I asked my lawyers to refuse, and we fought about it, repeatedly. They brought up things from my past that could be used against me; not criminal behavior per se, even they admitted, but they wanted me to have immunity."
Different people have different situations; no single piece of advice can apply to all people. Speaking for myself, if somebody placed me in a tricky position where my past could be used against me I would always put myself first if it meant protecting myself and my family.
Being a single mother is tough enough; being a single mother, struggling with money, involved in things you don't understand, being threatened by people with significant amounts of power (is it hard to believe eventually they would have done something to threaten her daughter?) would be enough to convince most normal people to speak. Given the information she had at the time she made a rational (debate-fully wrong) choice.
While there may be strong arguments for the case that the prosecutor's actions are unethical, ultimately Aaron's actions put her into this situation. His blaming her for her actions after being caught up in his battle, while wanting to protect herself and her child, is offensive to me.
It's sad that she beats herself up - she lost in a game she was not trained or skilled enough to win, a game somebody else forced her to play.