That's why some people fear trans inclusion. They are afraid they'll no longer have any turf to stand on. And so they fear losing those lesbian/gay borders. But it's important to remember that those demarcations do not depend on being able to clearly define each individual as lesbian or gay. These rough boundaries delineate the scope of oppression; these are the perimeters of collective fight-back.
Trans liberation is not a threat to any lesbian woman or gay man or bisexual person. Yes, trans liberation is shaking up old patterns of thoughts or beliefs. Good! Because most of those thoughts and beliefs that we are challenging were imposed on us from above, were rotten to the core and were backed up by bigoted laws. But we're not taking away your identity. No one's sex reassignment or fluidity of gender threatens your right to self-identity and self-expression. On the contrary, our struggle bolsters your right to your identity. My right to be me is tied with a thousand threads to your right to be you.
Leslie Feinberg, Trans Liberation: Beyond Pink Or Blue (pg. 101)