The Syndicate

Don't know how helpful this'll be since it's mainly based off of what I've learned in my Army/business classes, but I'd suggest going to your HR department and bringing up your concern there, maybe if possible get your former manager who helped you keep the job go with you, lay out your concerns say that you feel the work environment is currently hostile seeing who you'll be reporting to and come prepared to show all the work you've put in. I'd also mention to them that she's never directly addressed these concerns to you in a formal or informal counseling/review session which is really unprofessional/unethical for a boss. Which shows she's got a personal gripe with you or something.

If you don't have an HR department to go to I'd go to her boss, even with an HR type thing still keep her boss/the next level of management in the loop. Make sure your exchanges with HR/higher management is recorded so you have something to fall back on and I'd avoid being alone with your current boss and make sure to keep a record of conversation/emails. Just so she can't accuse you of something to try and get rid of you.