A transgender person can be gay, straight, bisexual, or asexual. A trans woman (assigned male at birth who identifies as female) who loves women may identify as a lesbian. A trans man (assigned female at birth who identifies as male) who loves men may identify as gay. The fluidity of these identities is a hallmark of modern queer culture, challenging the rigid binaries that have historically governed Western society.
To celebrate LGBTQ culture is to celebrate the gender outlaws, the street queens, the she's, the he's, and the they's who refused to stay in the closet. It is to understand that the fight for Same-Sex Marriage was a step, but the fight for gender self-determination is the destination.