From your story, I get a sense that Sue is in constant need for attention and self-validation, which makes her hostile towards anyone who poses a threat to her sense of security. I think she will continue her cycle of pushing people she likes away unless she reflects on her self-destructive behaviour. And for you, I don’t know how you managed to get through all that toxicity at the workplace for so long, but I’m glad it didn’t consume you.
You deserve an Iron Woman’s badge, TzeLin!