Would it be inappropriate to say goodbye to my therapist? I’ve had the same therapist on and off for 6 years (periods of time where I didn’t need the therapy), over a quarter of my life. She has helped me deal with heartbreak, anxiety, suicidal idealizations, depression, and so much much more. Soon I will be moving away for good. I kept seeing her because I went to college in the same town I grew up. 
I wanted to know if it would be inappropriate to write her a letter to say goodbye. I had to cancel my most recent appointment due to work, and don’t see the need to make another. I am not unstable or any of the sort. My depression was 5 years ago and recently went again to cope with heartbreak. 
She has helped me enormously, and I want her to know that.