The owner of a company that emailed my GM intimating that I am homophobic. Is this defamation?

The owner of the company, Michael J. Wilson, that runs the WINTER RENDEZVOUS Jan 20-24, 2016 Gay Ski Week - Stowe, Vermont visited our hotel lobby for less than 3 minutes. There was no communication other than a hello, and me indicating that I would let our GM know that he had stopped by to visit.

A few days later, my General Manager, questioned/confronted me about an email Mr. Wilson had sent him. The gist of the email was that Mr. Wilson felt I was a homophobe and treated him badly once I knew that he was the organizer for e gay event.

I feel this has created a negative perception of me in the eyes of my employer. I am an open-minded person and feel genuinely offended. More importantly, this is a small town and I'm afraid that my reputation has been harmed, especially if Mr. Wilson is recounting his story to others.