Well Dev, Doreen I can't say you're wrong (obviously nobody deserves toxic people), and like you I built distance - short of completely cutting ties but damned close - long before I realized I was trans.
Like you Dev, my daughters both advised against being out with their grandparent, as I said, that's not on the table but is in the back of my mind as it means staying closeted wrt 95% of my family.
Completely severing ties would also place a burden on my daughters.
What I've decided is to discuss the need to put some respect back into that relationship. In fact, I'm about to make that call, wish me luck.