Am I the bad guy?

I've been with my DF for coming up on 3 years from the get go I knew he wasn't a great pick for me but I had always had a huge crush on him in high school so I went with it. I always heard from my brother that he was a heavy drug user but I pushed those accusations aside and gave the relationship a shot. After 1 month together he proposed to me. After that it seems like everything went down hill...I've drug tested him 100's of times and he's always failed for everything and had an excuse to cover it up. So I let him slip by a few times. We found out in June that we were expecting which was extremely short lived because our daughter passed away safe in my tummy at 17wks. I feel like I should blame him because she had a bunch of problems all caused by his sperm not being all there because of his drug habits. It's now November, I've never stayed with sow ken who put their hands on me. He's choked me twice and bashed my head against the wall, grabbed my arms so tight that they bruised. I tell myself to leave by I can't. He's been sneaking around doing heroin and he failed his drug test today so I grabbed his sweatshirt while he was trying to run out the door he pushed me down and called his dad saying I hit him. He has turned his family against me even though I have all the evidence of what he's done to me. On top of all that, I found out I'm pregnant today. 
(His drug test from today pictures below)
My neck from him choking me
I need guidance I don't know what to do!!!!!