Like everyone is ultimately gonna say on this thread, I think you're a good person doing a fantastic job with your girlfriend.
I understand what's it like to take the bear of the pain that comes out of seeing someone you love so much hurting inside and outside of herself. It shows you got absolute strength for yourself and the total love for her.
Despite all the troubles you got with her, I'm sure she thinks of you everyday and thinks you're the best person to her. For her getting drunk and using any other means of substances, it happens and you can't exactly control that. When people are... severely depressed such as myself, people don't tend to think it through and just want total salvation from the mess we're in. I'm sure you understand that, she just taking it in extreme way. Sure, you can't control her actions in the future but you have the power to influence her thoughts and choices.
It's a long battle you two are going through and nobody coming out without scars from what you've recently said in this thread, but I swear to you that things will get better for the both of you as long you got that strength to keep going for her as well as helping her.
I wish the best of luck to the both of you
