If we're not supposed to "gender genitals" then what is a lesbian? What exactly are the parameters for being a lesbian? Even further, what are the parameters for any sexual orientation?

Let's say for instance there are two men in a relationship and they are both "gender fluid". Some days they would call themselves men and other days they would call themselves women. On the "men days" it's "he/him" and on the "women days" it's "she/her". Now let's suppose that there are a few days where they both call themselves women. Are we supposed to call them lesbians on these days? What if one is on a "woman day" and the other is on a "man day" are we supposed to call them straight on these days? What are the rules??

Gender identity politics is so confusing. Sometimes I wish I was never exposed to any of this stuff.