My boss is power tripping on me even i work very well in the company. can i file a case against her?

Start taping any and all your conversations with her. Can you prove the slander info? If so, take all this information to your HR department and file a complaint against this boss. Sounds to me that she needs to be "checked" real quick. Maybe your HR team can pull her coat tail based off the evidence you have...Then if you get no where with the HR department, proceed to the EEOC or the labor board within your state. You must follow your company's protocol before making a claim against your company with any outside legal organization.