I thought it was implied that Chapel was a brief romp, not a past romance, by how he didn't remember her. Yes he does remember past women he had romances with fondly. But I bet three months from the Caitian romp he would struggle to remember their names.
And then there was that awful deleted scene where he couldn't remember Gaila..
I thought he mistook another woman for Gaila. (Yeah, I know, not much of an improvement.)