I'd probably have tremendously less anxiety.
Also, I'd greatly enjoy telling people who, on hearing of my wealth, suddenly remembered I existed, to go fuck themselves.
Also, I'd want to contribute to making my grandmother's last years better. Without my grandfather, she has much less financially, and her dementia has progressed, and the whole situation's a clusterfuck. I'd talk logistics with my aunt on how to do this without having it just end up being me enabling my alcoholic uncle and his alcoholic wife who live with her.