Legal Question in Employment Law in California

I don't doubt your stress and overwork, but those are not grounds for a lawsuit. They are reasons to join (or organize) a union though.

You should consult with an employment law attorney about your options.

Step One: look for a new job.

There are no other steps, nor are there grounds for a lawsuit. .

Not only are there no laws against poor management, 'unfair treatment', or rude and obnoxious behavior, but in general unless an employee is civil service, in a union, or has a written employment contract, they are an 'at will' employee that can be disciplined or terminated any time for any reason, with or without ‘cause’, explanation or notice. Any employee's goal should be to keep their supervisors happy and make them look good to the company, and make the company money. That’s how the company pays employee wages. If you don't, then don't be surprised to be replaced.