I understand your mixed feelings. I guess I have feelings about people that have helped me cross a raging river.

Since it is a professional relationship, it might be appropriate to ask what the goal of therapy was and what you accomplished in therapy.

And what else is left to accomplish in the next situation.

Email contact would be nice, but some T's discourage contact after therapy is over.

I would write a letter of gratitude thanking them for what they did accomplish and how they helped you. Appreciation can be a scarce commodity. One letter of appreciation can outweigh all the hopeless patients they must face each day.

A big thank you sounds like a mature way to end one phase and begin another.