Sunny, 26, is a protester who takes to the streets to denounce what she regards as the oppressive policies of the central government in Beijing. Her husband is a low-ranking police officer, working 12-hour nightly shifts to confront the demonstrations his wife supports.

Since June, they have coexisted like this: standing on opposing sides of the barricades by night, and then parenting their two daughters together the next day.

They have witnessed the deepening rift on the streets that has come to define the struggle for Hong Kong’s soul. That fight is now driving a wedge into their home and the homes of families like theirs, and even into the ranks of the police force itself.

“In the beginning, it didn’t seem any different from any other protests that we have always had over the years,” Sunny said in an interview. “But now, we can’t even talk about any normal daily life. No one has the patience for it.”

As Hong Kong’s government has stepped up the pressure and arrests, increasingly violent clashes between protesters and the police have made the streets more tense. The divide between the two sides has grown.

Secretary for Security John Lee has defended the actions taken by the police, saying that the force remains the most professional in Asia. “Despite the dangers and difficulties they are faced with, they still discharge their statutory duties with courage,” he said.

In public statements, officials have accused protesters of harassing officers, and sometimes their family members, online or in person. The treatment by protesters has angered many officers, who now face regular criticism on streets where just a few months ago they were widely respected.

Sunny and her husband have known each other since they were children, and married five years ago. She asked that her full name not be published out of fear of retribution by the government or other officers.

She remembers how her husband cried with pride the day he graduated from the police academy.

“Back then, he thought it was a noble profession,” Sunny said. “But it turned out to be below expectations. In just a few months, he realized that the hierarchy was too severe.”

Each day her husband returns home, Sunny tries to talk him down from the tension he absorbs on the front lines.

“The conversations are not always peaceful,” she said.

“I keep telling him, ‘It’s normal to feel angry,’” she added. “‘But, no matter how furious you are, the law will punish them. It is not your job to punish. You don’t have to use any excessive force because you are not a torturer. You are a police officer.’”

Sunny’s husband declined to speak in person or give his name, but emphasized the gulf between the government’s demands and the protesters’ grievances.

“It puts so much pressure on me and my family,” he said by text message, adding that the police “have no choice” but to arrest those who break the law.

But he acknowledged that the authorities could improve their handling of the protests, and said that his wife reminds him of that.

“She keeps me in line,” he said. “She is always urging me to consider how police officers can regain the trust of the citizens.”

Through their negotiations, Sunny has come to understand how, on the street, the police have become a stand-in for a government that is increasingly loathed by the public. “It feels like we have a common enemy,” she said.

In July, she decided to organize a Facebook group, “Police Relatives Connection.” Its mission is to restore the public’s trust in the police.

“We are not part of the police force, but we are the closest to them, and they may be more willing to hear our voice,” she said. “If the wives step up, the citizens will support them.”

Most members of the Facebook group are just like her: They have a close relative in the police force but still support the protesters.

One member, Phillis, a 42-year-old social worker for primary school students, has been married to a police officer, her first love, for 21 years.

As she became more involved with the movement, she realized the man she had built a home with had become a stranger.

“We do not share the same views,” she said, speaking about her husband at a recent meeting of the Facebook group. “I have told him that once our kids are grown up, I am going to think about divorce.”

To avoid confrontation at home, she no longer watches television and saves political discussions with her daughters for outside the house, away from her husband, she said.

Of the officers who feel conflicted in their posts, few dare speak out while the force is under so much pressure and public scrutiny.

Cathy Yau, 36, had been in the Hong Kong police force for 11 years before resigning in July and deciding to step forward and take the risk of publicly criticizing the police.

Earlier in the summer, she was posted outside the Hong Kong Central Library, monitoring the demonstrators who were assembling across the street in Victoria Park. She recalls one particular march, on June 16, when protesters chanted “dirty cop” at her as they passed by. She identified with their anger, and at that moment she began to feel she might be on the wrong side of a conflict.

“As a trained police officer I knew what they were doing was not completely lawful,” Ms. Yau said in an interview. “But I also appreciated how they understood that if worse came to worst, they were willing to sacrifice themselves — their future prospects or even their lives.”

As tensions escalated through June, and officers began using force against protesters, Ms. Yau grew increasingly frustrated, she said.

“It got to the point where I couldn’t walk down the block to give a parking ticket without wearing full gear, and I finally thought, ‘What is the point to wearing this uniform?’”

She expressed a view that she said is becoming more common in the police force.

“I felt like the government was hiding behind the police force,” she said. “Many police officers are normal Hong Kong citizens when we take off our uniform after work. We are all H.K. citizens, but the government didn’t seem care that there is blood on the street.”

On July 10, she decided she had seen enough. She slipped her resignation letter under her boss’s door.

Ten days after she resigned, Ms. Yau watched a live-feed of a group of thugs in white shirts beating protesters in the Yuen Long train station as police officers — her former colleagues — failed to stop the violence.

“That was the first emergency call I ever made in my life,” she recalled. “The scene was horrifying, and hugely disappointing.”

Standing in her tiny apartment, Ms. Yau unfurled the certificate she received when she took her oath as an officer in 2008. Holding that piece of paper feels bittersweet, she said, after what she has seen this summer.

“It does upset me,” she said, referring to officers’ use of force against protesters. “Perhaps it’s difficult for them not to follow orders; but they can choose to act differently.”

After Ms. Yau went public with her story, several officers reached out to her, asking for advice on how they could follow in her footsteps, she said. One told her he was worried for his daughter’s safety and well-being. Another told her that he had fallen under suspicion from his bosses and had been asked to disclose his political stance.

Ms. Yau says she now wants to run for City Council in November.

“I decided I needed a new platform to do what I wanted to do,” she said. “It all comes down to whether there is a government that serves its people diligently and loves its people. People are that simple. They don’t want to go out and protest.”