Rude and offensive behavior is not legally actionable unless it relates to a legally protected trait, such as race, religion or gender. Being generally "mean" is not against the law and employers have no affirmative legal obligation to address such behavior, however unprofessional and understandably upsetting it may be.
Your facts do not suggest harassment on the basis of a legally protected trait (i.e. your coworker was not yelling racial slurs at you or making offensive jokes about your religion), and so you would not typically have any legal claim against her or your previous employer.
Best wishes to you moving forward.
This answer is a general interpretation of the law and is not fact specific to your case. Likewise it does not create an attorney-client relationship. You should seek an attorney for a review of your specific facts and documents.
Sorry but no. Most forms of what people consider to be harassment are not illegal. Unless the conduct directed at you was motivated because you are a member of a protected class of people, or because you engaged in some form of legally protected conduct, the harassment is perfectly legal albeit rude and angry.
Good luck to you.
This answer should not be construed to create any attorney-client relationship. Such a relationship can be formed only through the mutual execution of an attorney-client agreement. The answer given is based on the extremely limited facts provided and the proper course of action might change significantly with the introduction of other facts. All who read this answer should not rely on the answer to govern their conduct. Please seek the advice of competent counsel after disclosing all facts to that attorney. This answer is intended for California residents only. The answering party is only licensed to practice in the State of California.
I understand that you are having a very difficult time at work with your coworker. Unfortunately, from the information you have provided there are no legal actions you can take. You are only protected if you are being discriminated against based upon a protected class (race, religion, sex, national origin, age, and disability). The situation you described sounds more like workplace bullying which there are no legal protections against.