I really shouldn't allow this one incident to define him as a person in my mind.

This wasn't an incident, this is deliberate. Incident is when something terrible happens, an accident, medical bill, something really bad and the guy can't pay you as it has life and death situation to deal with. That is an incident.
What you're dealing with is pure selfishness! He has no values, that is clearly visible. It happened to me the exact same thing, just posted the story to your other post as I read that earlier.
These people don't deserve support.