Please help me understand if it was all my fault? I CANNOT live like this anymore?

I met this amazing man a year ago. He had just gotten seperated from a terrible marriage and I had just gotten out of a horrible relationship so we were friends for awhile before we started dating. When we gave into our feelings for each other we began the most amazing relationship I had ever known. We moved into the most beautiful loft and planned our entire future together. I did know that he had used cocaine and done pills before but he had stopped when we moved in together. All the boys that he hung out with were completely out of our lives. We did try x together a couple times but both agreed to stop. About four months ago I tried coke with him and realized I hated it. Then his mood started changing. We would fight all the time and he would take my key off my keychain so I couldn't even go home. I can be an emotional person so many times I would end up crying and then get blamed that this was all my fault. He could be jealous at times and one night I was so frustrated with putting in so much effort without getting anything back that I went to spend the night with one of my girlfriends. He called my 20 times in 40 min and then told me he changed the locks and I had to get out. The next day my father went with me and we got all of my stuff. I know for a fact that he has done coke at least 6 times in the last 4 months, and not sure if there's more. His mother has been calling me and asking me whats going on and I finally told her about the drugs. He's just been going missing and I won't hear from him for days, and we fight constantly. A couple days later he got fired from his job as the head chef of an incredible restaurant and blames me for it. Now he has convinced his mom that it was all my fault and she has blocked my number. I only told her about the coke because I think it has changed him. But now I miss him more than anything, I was supposed to spend the rest of my life with this man! He still hangs out with all of our friends and everyone loves him, and I feel so alone. I can't stop replaying everything and blaming myself. I just want us to go back to that perfect couple that loved each other more than anything in the world. He's told me that I have made up these stories about drugs in my head, even though I've been with him three times while he's done it, and know of at least two more for sure. Obviously he can function just fine while using, and maybe I have just created this dramatic story. I'm a very intelligent woman but I'm so lost and confused. I want my boyfriend back, the only man I've ever felt like this for. I want us to be happy again, with no lies. Is this all my fault? Am I just overreacting? Please, please help me.....