Let me try to clear this up. On this site we use the following definitions:
Transgender: an inclusive umbrella term which covers anyone who transcends their birth gender for any reason. This includes but is not limited to Androgynes, Crossdressers, Drag kings, Drag queens, Intersexuals, Transsexuals, and ->-bleeped-<-s.
In my case, I'm a crossdresser. This means I'm transgender. I choose to dress, so for me, being transgender is a choice.
Someone who is born transsexual, would usually not consider it a choice. But they are transgender, too.
And all the non-binary, genderfluid, genderless people, too. They're all transgender. We all are, heck, we have cisgender members, too. Hugs, Devlyn