A Yemeni protester flashes the victory sign during a demonstration Monday in Sanaa against the Shiite Houthi rebels who have overrun the capital. (Mohammed Huwais/AFP/Getty Images)

For Faizah al-Sulimani, the hope stirred by Yemen’s Arab Spring uprising has long since faded.

Four years ago, she joined the wave of nonviolent demonstrations that rippled across the Middle East and led to the ouster of entrenched autocrats, including Yemen’s Ali Abdullah Saleh. Sulimani’s optimism, however, quickly turned to bitterness over what followed — a post-revolutionary order that she and many of her fellow Yemeni protesters consider as corrupt and inept as the one they had struggled to overturn.

Yet, even they never imagined that things would get this bad. A civil war looms after Shiite Houthi rebels deposed the government last month and dissolved parliament. Many Yemenis fear that the resulting political vacuum offers extremist groups, including the powerful local affiliate of al-Qaeda, an opportunity to exploit.

[Chart: Yemen on edge after government resigns amid widening unrest]

This has left Sulimani and her fellow 2011 activists despondent and feeling more marginalized than ever.

“After all that we did, we have reached this point — Yemen collapsed,” Sulimani, 32, said in an interview this month in Sanaa, the capital. “There’s violence in the streets. There’s chaos. Nobody knows what’s going on anymore.”

In the heady days of 2011, she played a central role in coordinating media communications for the protesters. She distributed fliers and kept tallies of abuses by security forces. Often, she recalled, there was only enough time to squeeze in two or three hours of sleep at night.

[Archive: Road to revolution]

Inspired by uprisings that deposed Tunisian President Zine el-Abidine Ben Ali and longtime Egyptian strongman Hosni Mubarak, Sulimani was taken with the idea of using nonviolence to upend an ossified political system that had failed to meet the aspirations of Yemen’s burgeoning youth population.

These youths, from diverse backgrounds, rallied for more jobs and an end to corruption. Some were fatally shot or beaten by suspected Saleh henchmen. But despite the violence, the protests spread nationwide because of a shared desire for democracy.

“We went to the streets full of hope,” Sulimani said. “We had a dream of revolution.”

Now, her revolutionary zeal appears grounded by reality. She works for a local development agency and wants to put off marriage to pursue a master’s degree at a university in Britain.

She dismisses the idea of returning to the streets to protest Yemen’s current predicament. As in the aftermath of 2011, she said, the old-guard political and business elites would again exploit the rallies for their own ends.

“We were used as tools by our politicians,” said Sulimani, her face fully veiled. “We can’t let that happen again.”

Scores of activists have chosen to emigrate rather than struggle for dwindling opportunities in a country of about 25 million that is wrestling with nearly 50 percent unemployment and grinding poverty.

More than 10 of Mutte Dammaj’s friends who rallied with him four years ago in Sanaa left the country after the uprising, mostly to Europe, he said.

“There is deep despair,” Dammaj said.

He also expressed concern that the prevailing sense of hopelessness could push more young Yemenis into the arms of al-Qaeda, as well as secessionist groups in the south.

Still, small protests continue as activists stage demonstrations against the Houthi rebels.

Samia al-Aghbari, a 33-year-old activist, attributed the rekindled protests to the defiant spirit that the 2011 uprising helped instill in Yemenis, especially women. They were inspired by Sulimani and other female protesters, such as Tawakkol Karman, to overcome many of the barriers of their conservative culture. Karman won the 2011 Nobel Peace Prize for her nonviolent struggle.

[Read: Tawakkol Karman in conservation.]

“People used to question why women would step out of the home and demonstrate,” Aghbari said. “You’d hear them say: ‘Aren’t men strong enough to do this on their own? Why should a woman have to get involved?’ Even my family would tell me that.”

“That’s not the case anymore,” she added.

Aghbari acknowledged, however, that nonviolence would be difficult to sustain against the Houthis. Activists and human rights groups have accused the rebels of systematically targeting protesters in the capital with death threats, abductions and severe beatings.

[Read: Who are the Houthis?]

Ahmed Abdo Ali, 28, said his fellow 2011 protesters are increasingly concluding that Houthi violence has to be met with force. “You’re seeing the situation becoming a military conflict,” he said. “It’s terrifying.”

That prospect, Ali said, could undo all that he and others like him fought for four years ago. He recalled how Sulimani remained committed to peaceful tactics even after six police officers dragged her out of a car in July 2011 and beat her with rifle butts. Soon after the incident, Ali said, she called to reassure him.

“I remember her insisting: ‘I’m fine. I’m fine. Just keep going and I’ll be okay,’ ” said Ali, who described her as a “super-activist.”

More upsetting for Sulimani, however, is the lingering pain from March 18, 2011. That was when men in civilian clothes opened fire on protesters in Sanaa’s Change Square, killing 45 people and wounding 200.

Six of her close friends were killed that day, including 28-year-old Abubakir Ali. Two days earlier, he had virtually predicted his own death, Sulimani recalled. “He told me: ‘Please, if something happens to any of us, the rest of you should continue. This is our future and our country, and we have to protect our country,’ ” she said.

Sulimani and many others accuse Saleh, who ruled the country for more than three decades, of orchestrating the attacks that killed hundreds of protesters during the uprising. Instead of legal proceedings, however, a power-transition deal that was backed by neighboring Arab countries and the West offered him immunity in return for stepping down.

In January 2012, parliament approved the deal, which also allowed Saleh to stay in Yemen.

“I just cried when I heard about the decision,” Sulimani said. “All the sacrifices and all the people we lost. Was this all for nothing?”

Since then, Saleh has been widely accused of helping the Houthis foment the ongoing unrest in Yemen. In November, the U.N. Security Council imposed sanctions on him, saying he had destabilized the country.

Sulimani keeps telling herself that the people of Yemen must not forget the sacrifices made to force out Saleh in the hopes of building a better future. During the interview, she showed six bullets that she carries in her purse. They were fired by security forces during the uprising, and she keeps them as a reminder.

“These remind me that I have to continue to strive hard, not to give up,” Sulimani said.