You seem to be very concerned about other people
But the concern you appear to have is what they'll think of you rather than being concerned with what you think of yourself. Your fil and your AH are basically running your life. Now you're asking here what you should do. I'm afraid nobody is going to tell you what to do because nobody else is living your life. I'm sure you'll have people tell you they can relate with what you're going through and may even tell you how THEY coped with the situation, but nobody is going to give you an answer to your situation.
You can choose to literally walk away from your fil when he starts yelling, you can yell back at him, you can ignore him, you can tell him to butt out, or probably any number of other responses - but it's YOUR choice.
I can understand you want your children to stay in decent schools, but I guess your aware that you're raising what will someday be adult children of an alcoholic and although kids are quite adaptable, there is a higher incidence of any one of them having a marriage that ends in divorce and/or marrying an addict when they grow up. That doesn't mean it's bound to happen, it's just that the odds are higher that it could.
I understand your frustration with nothing getting done - or only half-way done - around the house. My garage door has been broken for three years and I still listen to "I have SO MUCH to do," "I NEED to make a dentist appointment," "I HAVE to bring in the porch swing before it turns cold," blah, blah, blah. Mine spends most of his waking hours drinking and then taking "naps" throughout the day. As the disease progresses, an alcoholic becomes more focused on getting and consuming their addictive agent. If push comes to shove, an addict will pick the bottle over anything else. Period. Hey, it sucks and I get frustrated and depressed about it more than I should, but I have choices I can make. Believe me, it's tough to get up every Saturday and Sunday morning to find my AH started taking shots of scotch when he woke up so he's already half-bagged by noon. And this goes on day after day after day. I have financial reasons for staying, but other than that I know I can choose to leave if I want to at any time - or at least as soon as I have a job and can afford to move out.
You're the only person who can live the life you were given. You have some hard choices to make. I hope you find the serenity and hapiness you seek when you make those choices.