You are in an incredibly difficult position, and I appreciate that. And I don't believe anyone in your brother's impossible position is culpable for doing what he needed to in order to stay alive and solvant. But there are the more cut-and-dry cases, we all know them, and maybe your family denial falls into that, that's a burden I don't envy, and I hope you are supported by your community in it.
Talking about the harm, the division, the feelings from it, didn't create it. If we are going to mend as a society, it won't come from stuffing all this down and pretending it's not there. I mean it when I say I don't know how to forgive the covid deniers, the ravers, (we had a fair few of illegal raves over here), the antimaskers and antivaxers. I don't know if we can mend in this generation, I don't know if I can mend. I am not kidding when I say lie to me. But I also don't feel like I have to go the whole distance on science denial and make all the allowances, or that I can. We all have to pick our battles.