family dollar Store manager / human resources discriminating against my mental illness and taking advantage, workplace bullying, not paying my overtime myrtle beach South Carolina

 I have worked for family dollar for 4 years now. The problems that I'm going to talk about started happening about 2 years ago when I was promoted to a assistant manager. I was hired in with the store manager and district manager knowing I suffered from mental illness and was being medicated for PTSD and depression. My store manager took advantage of my disabilities and started bullying me daily. I was forced to work off the clock going to the bank, taking conference calls every week and being forced to be on call on my days off because people always quit and I would have to come in so she wouldn't have to work a double. I was being threatened daily by her constantly being told if I could not do something she asked then she would look in the system for someone who could. I am a single mother of two boys one of which also suffers from mental illness and is medicated so I could not afford to lose hours or my job. She continued to find more ways to take advantage and I found myself doing most of the work by myself. I started suffering from panic attacks and found my depression was worse and my medicine no longer was working. The verbal abuse and intimidation continued until I suffered a nervous breakdown. I was let go because I could no longer function. I stopped leaving my house , eating, and I can't stop crying. I reported the time they owed me for to the head of human resources and she worked with the district manager and knows I worked off the clock but she said she has to investigate how much to pay back for the 2 years. The problem now is she told my old store manager and I am still being bullied by her even though I am no longer with the company. She has rode by my house 3 different times , began slandering my name to customers I been with for 4 years and they call me almost daily letting me know the disgusting things she is saying. I tried calling the head of human resources and left voice mails but I'm not getting a call returned. I just want this to be over with so I can go on with my life and start to finally be happy again. Now I'm not sure there going to do anything for me anymore. How can I make sure I get the money owed to me? Where can I turn for help? I have no money for a attorney and I have never gone thru this at a job before. Someone please give me advice. Thanks for reading