I'd leave his girlfriend out of it. It isn't her JOB to keep track of his drinking. What I think I WOULD do, though, is to tell her you're concerned about some of what you've seen/heard, with her crying and so forth, and tell her that she should feel free to come to you if she ever needs help. She might not now, but based on what you've posted before, if she stays with him she is likely to need help at some point.
What you've posted before about his behavior I find VERY alarming. Just because others are bent on enabling him doesn't mean you have to. You can stop rescuing him and work on detaching. Are you going to Al-Anon?