Zevan was a loyal changeling and always did his queen's bidding, although he quietly questioned why changelings should end centuries of secret but peaceful intermingling with the pony population. After being expelled from Canterlot by the irresistible force of love and badly injured after crash-landing in trees, he had to reconsider his future. Ponies knew that changelings existed now, and the only example of them was Chrysalis' attempt to overthrow Celestia and their attack on Canterlot's population. His kind would be pariahs for the foreseeable future and maybe even their disguises would not keep them safe. A unicorn mare with a broken horn might do the trick though.

There is now a prequel to this story - Prelude To Change I suggest that you read that first.