I thought his response was cordial and appropriate. In contrast, your email seemed kinda harsh! It's easy to miscommunicate by email.

I think your termination of him might have been better done in person or by phone. That allows you to connect better and end things the way you want them to end (sounds like you were seekly more from him than just a polite email response and you felt dissatisfied when you didn't get something more).

If it were me, I wouldn't have terminated at all. I would have kept him in reserve for if I decided I needed pharmaceutical help again in the future. Just like with my family doc. My health is pretty good, so I may not see my doc for quite a few months. But she is always there when I do have a concern and need to get an appointment. I don't need to terminate with her just because I don't plan to see her regularly.