If she ended via text message, but that was the only time she was hurtful, I would ask about it, and process it with her. Tbh it sounds to me like there are a great many reasons to go back to her, and I very much assume that if you explain the situation to your current T, also about the possibility to see ex ex T in person, I'm assuming she'll understand, because her interest ought to be to enable you to chose what is best for you