@David1157
As a frequent budget traveller I can relate to your frustration. If I were in your shoes, I'd probably feel as bad as you, but that's the thing with strict cancellation at Airbnb or non-refundable tickets/hotel reservations. You need to be ABSOLUTELY sure before you pay, and in case of plane tickets or hotel reservations, non-refundable is non-refundable. That's why when I was an Airbnb guest, I never booked places with strict cancellation.
I'd suggest that you politely approach the host again and ask, if they are able to book diffferent guests during the time you booked and cancelled, please consider providing at least a partial additional refund.
As a host, I had a guest instant book with me for a week 4 months away from the time of booking. I was messaging back and forth with a different potential guest at the time with overlapping date(that I was really hoping to host), so I sent the IB guest a message immediately (like 3 minutes after getting the booking notification) appologizing, asking him to cancel and find alternate accomodations. I recieved a "Guest requests that you cancel" message about 10 minutes after. I clicked on "cancel" which made it a host-cancellation. My first review EVER on Airbnb is now "The host canceled this reservation 139 days before arrival. This is an automated posting." I still got penalized as a host for cancelling a booking less than 30 mins from the booking being made and 139 days prior to the reservation, and my commitment rate took a big hit.