Also, before she gets too comfortable with the comparison between being poly and being gay, you might want to remind her that generally, if one has been "living a lie" about one's sexuality, the current relationship does not withstand the change to honesty. It is a rare heterosexual couple that survives one half coming out as homosexual. While you may still love her, what she now wants is not the relationship you agreed to participate in, so she should be careful about pushing too much too fast. First you need to decide if you're even willing to TRY to participate in a poly relationship, and then what that will look like for the two of you (boundaries, expectations, etc) before she takes ANY steps to actually "practice" polyamory.
Pan Female, Hinge in a V between my mono (straight) husband, Monochrome and my poly (pan) partner, ThatGuyInBlack