Your journey has been really painful. I don't believe you did something very horrible, or in itself cause for such a sudden termination. It also seems like the dietician plays a dubious role in the communications. I wish you could find a new dietician, to get away from the reminders and a new T. I wonder if your T had been thinking for a while she wasn't helping you. My close friend is a clinical psychologist , and she went to a conference on the shame some T's hold when they fail to help. I d believe you can move on fro this place of focus on your ex T, but you're going to need devoted relational experience with someone else to do it. Do you have a dog or cat? Part of the obsession might possibly stem from the power imbalance? It is a very strange thing when an essentially human relationship has a power imbalance built in, and it is a scary feeling being on the out-of-control end?