Married and sex went down since

So I got married a little over a year ago. We have been together for 6 years. Most of our relationship has been me alone. He has been in and out of jail/prison or drug treatments. I love him soooo much but he uses drugs and then starts talking to other girls watching porn and really just shuts me out. I feel alone even when we are laying side by side. Our sex usually is only fun and exciting in times when he is using otherwise its like hurry up and get done kinda thing. He rushes through and then throws his clothes on and leaves the room. I used to do drugs with him also but have moved on from all of that it takes everything from you and I mean EVERYTHING. I was pregnant a year ago and it was an ectopic by the time the doctors finally listened to me that something was wrong I had a ruptured tube and was bleeding internally. They had to remove my left tube. I have tried to get pregnant since and have been unable. I feel like I am a failer all around my marriage is not what I thought and I cant give my husband a child. I have two children already from my last marriage. I dont want to have to start over I believe in my husband to be able to let go of the addiction but at what cost of myself before I have nothing left to fight for.