Dear tom647:
Wikipedia’s definition of toxicity: “Toxicity is the degree to which a substance can damage an organism”
So yes, the relationship was toxic as it either damaged you or had the potential to damage you if you stayed longer. When she is not distressed, as in when she sent you that email, she is reasonable and conscientious, concerned about your welfare and what is fair.
When she felt anger at you, she had the intention to hurt you proceeded to attack you by choosing and verbalizing words that will hurt you. That was her intention, to hurt you.
You walked on eggshells, meaning you were afraid of coming attacks by her. Living under the ongoing threat of being attacked by walking on eggshells around the attacker-to-be does damage a person.
People often misunderstand this point: it is most often people attack others when they are distressed, same as other animals. This is the normal for attacking: distressed precedes it. The fact she didn’t attack when calm does not mean she was not dangerous to you.
What makes a person damaging and dangerous to another is when the person, under distress, attacks.
anita