Do I have sufficient grounds to sue my ex employer manipulated me?

This would take hours to fill in each detail so I will tell it as I saw it and have back up. Promises were not kept. Lied to manipulate. On business trips, the manager would hire prostitutes, which offend me greatly knowing he has a wife and kids at home. I did express my view to him to no avail. One trip, we had a lunch with prospective business associates and he started to drink scotch. I told him we still had work to do, and that he should ease off, but he had quite a bit, gave me some remarks in front of these businessmen then when we went outside he slapped me in the face. It wasn't full force but it stung. I told him not to ever touch me again. He then slapped me again. I told him I'd pay him back in my time. Neither would visit the office about once a month and every time he did, he requested that I get drugs. I am a recovering addict. He knew that but he extremely persistent and I was weak. So each time he came down, the same thing occurred. The last time was 10 days ago. This time he had been away 2 months. I was clean and I gave in with him again. He stopped by my place uninvited. The next day at work, I was upset, ashamed and when he came in, I waited for a chance to tell him I wanted to see him outside to kick his ass, name calling went on then I was fired on the spot. He calls my customers and tells them I'm out of control due to drugs, and calls my landlord and tells her I am dealing drugs from my place. He has caused me a lot.