I too believe, Notso, that the situation with your brother is completely untenable for you. To be honest, the way he behaves in your home - and especially given that you've taken him in when he was in a bad place after the death of his son: that kind of carrying on is unacceptable for ANYONE to put up with.
In one sense, try to picture it if someone ( a friend, say) was telling you about being treated like dirt in this way at home - REGARDLESS of whether that person / friend is going through early sobriety, late sobriety, or just 'ordinary' life, with no particular addiction problems. See where I'm going?
This kind of stuff is sheer abuse. You do not have to endure it. Family members in particular can be outrageously exploitative, particularly of us women in the family. And it's especially cruel and thoughtless of your brother to be carrying on like this when he knows full well that you're trying to get and stay sober, and that you're therefore in a very vulnerable state yourself.
If he's in a shocking state himself, because of grief etc, that's sad. But if you tell him he has to find somewhere else to live, he can in fact do that. He can seek any supports - even for housing, counselling, etc - that HE needs to get. He does not need to be dragging you down with him.