Not a Bartlett, but I've had two (male/female) Lyretails and they rarely stayed together, the female tried to stay away from the male, cause he would lightly chase her. I also had a trio (1 male/2 females) Lyretails and similar results, male would swim in the open and female stayed in opposite corners. Had single Lyretail males twice and both times they were fine.
I was worried when I added the Bartlett to the tank with the single male Lyretail, but he never really even bothers the Bartlett and both are always out in the open. Can't say this is the normal, but it worked for me. Good luck, they bring nice coloration to the tank and are very active.