No offense, but you avoid conflict so no one hurts your feelings, her wanting to hash something out and be done and over with it doesn't make her a bad person as opposed to what, dragging it out and rehashing it over and over again for months? You both seem kinda petty. You spend too much time with a person you previously had a really good relationship and had fun going out with and talking, but because she pissed you off you suddenly have absolutely nothing in common and you can't stand her? Spending a lot of time with someone can make you aware of a lot of flaws, this is absolutely true, but to just write her off as someone you never liked or had anything in common with seems really two faced. She doesn't sound like that great of a person either, but you're not coming off much better yourself.

If you really want to be done with her, just ghost her since you'd rather avoid any conflict and potential talking and be done with it. If she tries to contact you, just ignore her and don't respond and move on with your life. You made her sound stuck up and stuck in her ways so it's probably better for you both to just let it end.