You're aware Transvestites don't think they're the opposite gender? They do it, normally as an act, in many cases transvestites do it for a living.
The majority are comfortable in their birth gender.
You may have meant transgender (mainly because the actual word would be filtered) who are born one gender byt identify as the other, they're not "pretending" anything, they >are< the opposite gender, if I girl was born a boy she is still a female.
js.