Is it normal that my girlfriend kisses her bestfriend
So I'm 16 and have been dating this girl for about a month and a half. Before our friendship turned into a romantic one we were best friends talking on the phone for hours and telling each other everything, which we still do now. Oh and also i was her first kiss, or so i thought.....However tonight my gf told me that sometimes she and her other best friend (who's a girl) kiss sometimes. She says it's not full on making out and that they only use a little tongue. She says she's not a lesbian (which I believe) I think it's just a phase. But I was wondering if someone could explain to me why she kisses another girl if she has no sexual attraction to them. I don't know why but finding this out made me feel weird. Idk I guess I just feel like it still is cheating but I don't want to over react or anything. Any ideas are much appreciated, thanks.