Cross-dress

Because cross-dressing behavior runs radically counter to most present day norms, it is most often interpreted as either transgender or homosexual behavior, when in fact according to statistics, it doesn't reliably reflect either of them.

The vast majority of human beings, like most of the animal kingdom are sexual creatures and apparently most cross dressers simply cross-dress because it sexually excites them, and doesn't mean that they want to be a member of the opposite sex or have sex with one, or many of them.
For a great many cross-dressers, or sissies as they are often unkindly called, the need to crossdress becomes a part of their very selves, in the same way that most musicians need to play music, or writers need to write etc.

It would seem however that cross-dressers are no more likely to become transvestites, than transvestites are to go on to trans-sexuality, or casual drinkers of alcohol are to become alcoholics, and present research suggest that the sexual factor involved in crossdressing tends to decrease over time, and that the major adjustment problems that crossdressers need to face are societal attitudes.