I think your very real life illustration of how people get treated differently when they suffer mental illness really brings home the point that mental illness really isn’t treated as seriously as other illnesses and injuries. I don’t really have much advice on your situation, because I feel like I might have some bias. I have family members who suffer from bipolar disorder and they will often say and do things that are really hurtful, and sometimes physically violent. As much as I try to understand that they not well and sometimes don’t have control over what they say and do, when hurtful actions/ violence have been taken out upon me it has really damaged the relationship between me and these family members. I have also hidden much of my own struggles with mental illness as a direct result.
So even though I have this difficult history, I think it’s quite unfair to hold a mentally ill person responsible for all of their “poor” behaviour but at the same time I have to admit that I hold conflicted feelings about this because of my own experiences. I don’t know if this is helpful at all, but I wish all the best for your mum, your aunty, your family and you.