Why the hek did Margaret do this?

Now, I know Margaret and Bern had a very passionate yet toxic relationship that they approached very doctorly and maturely. But, I watched this show multiple times, and still can’t understand why she would do such at thing? Why did she turn completely insane after he died? Speak ill of him, and ill of her children? I think I loved Margaret the most on this show, and was almost angry half of the time at Brenda for telling her mother off, but this thing she did must’ve been the most insane sht she’s done.

Now, I know Margaret and Bern had a very passionate yet toxic relationship that they approached very doctorly and maturely. But, I watched this show multiple times, and still can’t understand why she would do such at thing? Why did she turn completely insane after he died? Speak ill of him, and ill of her children? I think I loved Margaret the most on this show, and was almost angry half of the time at Brenda for telling her mother off, but this thing she did must’ve been the most insane sht she’s done.