Rose, I'm glad you're letting yourself feel the sadness. I know it hurts, but the way out is through.

When my first T told me he was leaving, I was devastated. I'd just come to a point of trusting him. I cried every time we talked about him leaving and every time I thought about it outside of sessions. Like you, we took the "celebrate and think positively" approach and the solid foundation he built served me well with my next (current and hopefully only other) T.