The conflict has raged at some women’s colleges and has been explored in academic articles, in magazines for lesbians and in alternative publications, with some — oversimplifying the issue for effect — headlined with the question, “Is Lesbianism Dead?”

It has been a subtext of gay politics in San Francisco, the only city in the country that covers employees’ sex-change medical expenses. And it bubbles to the surface every summer at the Michigan Womyn’s Music Festival, a lesbian gathering to which only “women born as women and living as women” are invited — a ban on transgendered people of either sex.

Barbara Price, a former festival producer, said the uneasiness has been “a big topic among lesbians for quite some time.”

“There are many people who look at what these young women are doing, and say to themselves, ‘Hey, by turning yourselves into men, don’t you realize you’re going over to the other side?’ ” she said. “We thought we were all supposed to be in this together.”

Beyond the political implications, the sense of loss is felt most keenly in personal relationships.

“I am a lesbian because I am attracted to women, and not to men," said a 33-year-old woman who broke up with her partner of seven years, Sharon Caya, when Sharon became Shane. The woman, who asked to be identified only as Natasha, to protect family members who are unaware of her lifestyle, said that she was ultimately faced with the reality of her sexual orientation and identity. “I decided I couldn’t be in a romantic relationship with a man.”