BOSTON – When Massachusetts started marrying gays and lesbians in 2004, activists giddily predicted the narrow court victory would speed same-sex nuptials nationwide, with state after state jumping on the gay wedding bandwagon.

Then the honeymoon ended.

More than two years later – and after recent court setbacks in New York and Washington state – Massachusetts remains the nation’s sole gay marriage safe haven.

The twin rulings were dispiriting blows for activists who hoped the states could provide a new bulwark for same-sex marriage. Opponents of gay marriage said the decisions are further proof Massachusetts is out of step with the nation.

“We would rather have won than lost, but things are not as grim as people think,” said Lee Swislow, executive director of Gay & Lesbian Advocates & Defenders. “We’ve had to remind ourselves of that.”

On July 26, the state Supreme Court in Washington voted 5-4 to uphold a state ban on gay marriage, overruling two lower courts. Weeks earlier, New York’s high court similarly ruled that a state law limiting marriage to between a man and a woman was constitutional.

Gay marriage supporters say they are hoping other pending court decisions may reverse the losing trend.

Top of the list is New Jersey, where the state’s high court is weighing a challenge to the marriage laws brought by gay couples, similar to the challenge in Massachusetts. Activists have high hopes for the state, which they say has a fairly liberal court and strong anti-discrimination language in the constitution.

They’re also keeping a close eye on Maryland, where gay couples are hoping to convince that state’s high court to lift prohibitions on gay marriage.

The biggest battleground may be California, which also has pending court action. California lawmakers approved gay marriage in 2005, only to have the bill vetoed by Gov. Arnold Schwarzenegger.

Matt Foreman, executive director of the National Gay and Lesbian Task Force, said there was a lot of “wishful thinking” in the heady days after Massachusetts’ historic court ruling.

“Many people thought the Massachusetts breakthrough would lead to a wave of other states extending marriage equality to gay people, but that’s not the way major changes happen in this country,” he said. “It’s going to take at least 25 years before there is significant protections for gay couples in most states.”

Foes of gay marriage also see the Massachusetts decision as a breakthrough of sorts – one that has galvanized backers of traditional marriage and fueled the push for new laws and constitutional amendments banning gay marriage.