Idk what to tell you either. I struggle daily dealing with my bf the same way. I've kicked him out several times and it doesn't do any good. If I think about it too often I want to kill myself. I hate feeling used and like I'm not important. But how does he think we can have a future, marriage, children, when I know he will never put me or a family first. Marijuana owns his heart and soul. He tries to say it won't kill him and isn't that bad but is. He has to hang around shady people to get it. It alters his personality and judgement. Im terrified he will bring home diseases to me or cheat on me. After all, bad people do drugs, so what's to stop them from doing other bad things? I just try to live in the present and not think about it. I worry about me.
Your gf couldn't trust you and you had an unhealthy codependency. She felt used and hated herself, likely everyone in her life hated you and encouraged her to break up . But then the only person who loves her was gone. Clearly she didn't love herself. She died for nothing because clearly you will never change. You will go on back to what you were doing and be fine and no one will notice or care. I wish men weren't so weak and women weren't so stupid. Sorry for your loss.

I don't want to seem harsh but, no woman can fix an addict. Recovery for an addict must come from inside. Life is full of choices and, with those choices comes consequences. I am very sorry for your loss. Most people strive to be "fixers" but, in reality, we can't fix everything. I helped wreck a marriage years ago due to Biker Gangs, and alcoholism. I too, have many regrets and many emotional scars from my younger years. I hurt a lot of people, emotionally and physically. Now, I have been drug and alcohol free for 46 yrs. this coming Sept.

Man. Sorry to hear. Do you have a group that can help you step out of this? I know some churches have groups to help people break through addiction and grief. Prayers that you can find some people to help you during this difficult time.