need to vent because its driving my crazy

My long distance bf and i trust each other 100%. But lately he keeps saying "this girl" or "shes coming to help with hw" which i dont mind him having girl friends but its starting to sound like hes trying to make me jealous. I never do this to him or talk about guy friends since i dont need to make him jealous. How can i get this to stop without indirectly telling him?