I noticed that part 3, your description of your brother in law's drinking habits, is the longest portion of what you wrote. I know that I focused on what other people were drinking, whether they were drinking, how much they were drinking to deflect my attention away from my own drinking.
I found it easier in the long run to focus on my own recovery. Let your continued sobriety be an example to your brother in law so that when he is ready, he can approach you for support. Until then, it's likely that your suggestions fall on deaf ears. I know it did for me.
Be well.