Explanations (as opposed to excuses) are good, because acknowledging what we react to and how we reacting inappropriately is the first step in correcting your first instinct (which, when in a mental break or spiral is usually defensive, self sabotaging, or an attack).
A lot of people will read something like this and go "That's still not good enough." But it's a starting point. Many people are horrible at self evaluating why they react the way they do when they feel emotional. It sounds like she is learning how to correct those initial reactions, and eventually she'll completely replace those with healthier responses without even having to try.
You two are very lucky you both sought help when you did. And as a fellow anxiety sufferer, I'm proud of you both. Let's keep working on it.