BOISE, Idaho — Lawmakers next door in Washington State just voted to legalize same-sex marriage. Here, they will not allow a bill to be formally filed that would protect gay people from basic forms of discrimination in areas like education, employment, public services and real estate transactions.

Next door, the lawmaker who leads the Senate’s most powerful committee, Ways and Means, is the same one who led the gay marriage bill to passage. The lawmaker, Senator Ed Murray of Seattle, is gay. In the final floor debate, he invited all of his colleagues to his wedding.

Here, the lawmaker who has spent eight years working for what might seem far less controversial goals is the only openly gay member of the Idaho Legislature. Now with the session well under way and a gay rights bill again showing little sign of getting a hearing, the senator who has been its champion, Nicole LeFavour, plans to become the former only openly gay lawmaker in the Idaho Legislature.

Ms. LeFavour, 48, has decided not to seek re-election, for what she says is a very painful reason: she has had enough and she expects things to only get harder.