The time has come to say goodbye.
So soon. It seems as if you just got here.
I feel that way, too. But all good things must come to an end, as they say.
It certainly has been a pleasure seeing you again and renewing old memories.
I've had a delightful time and I really appreciate your spending so much time showing me the sights.
It was fun for me, too. It gave me a chance to get away from my routine and do something a little different.
You'll be out to see me next year, as you promised?
Oh, yes. I should be there sometime next spring.