In 1952 the first U.S. transsexual story was told. Christine Jorgensen an American GI named George Jorgensen traveled to Denmark to have a sex change operation. Christine then returned to the US to be a model and author. This has produced little if any change in their internal feelings. Transsexuals seek to change their body because there is not an effective way to alter the mind to match the body.
Transsexuals suffer from gender dysphoria.
The gender dysphoria can be extreme and it's not uncommon for transsexuals to turn to suicide or self-mutilation. Some transsexuals may cross-dress but for the majority, this alone is not enough and they turn to hormone treatment and sometimes, sex reassignment surgery. Transsexuality is about a person's sense of their gender. Homosexuality concerns sexual orientation. People in transition are aware of the discomfort that others feel and try to work out the best accommodations for everyone involved.