As a 19-year-old girl in northern Iraq, Farida Khalaf had as normal a life as one could: She lived with her parents and four brothers in a small village called Kocho. She tended the family’s garden. She went to school and learned to drive. She celebrated holidays by sleeping in and hanging out with her best friends, looking at fashion magazines and braiding each other’s hair.

Then the rumors began: ISIS was coming.

It was the summer of 2014. ISIS had taken Mosul, the second-largest city in Iraq, and was on the move. Farida’s family lived over 40 miles away.

“They certainly won’t get this far,” her father told her.

They did.

‘We’re your new masters’

In her new book “The Girl Who Escaped ISIS,” co-authored by journalist Andrea C. Hoffman, Farida offers an incredible account of what global jihad looks like from the inside. Before ISIS ever invaded her town, she and her family only knew what they saw on the news, which wasn’t much.

Farida’s family, like most of the townspeople, were Yazidi — monotheists whose religion has roots in ancient Mesopotamian beliefs, and who’ve long been persecuted by Sunni Islamists.

Farida will never forget the date: Aug. 15, 2014. She was up on the roof at daybreak, and as the sun rose over the horizon, she saw them.

“Thirteen vehicles approaching our village,” Farida writes. “Not rickety pick-ups . . . but new, white vehicles, mounted with heavy-duty military equipment on their rear beds. In each of them sat ISIS soldiers dressed in black. In total panic I ran downstairs into the house and informed my father, ‘They’re coming, they’re coming!’ I cried. ‘They’re coming to kill us!’”

Her village had only heard of ISIS two months prior.

There was nothing anyone could do. Dozens of men in black drove in and took over, and that very morning, the entire town of 1,300 people was ordered to gather at the local schoolhouse at noon sharp.

“Bring all of your valuable possessions,” they were told. “Everything of value: cash, gold jewelry. Your cell phones. ID papers and credit cards too. Bring it all.”

“When there’s nothing more for them to steal,” her father said, “they’ll soon lose interest in us.”

When Farida’s family approached her schoolhouse, all their worldly possessions in tow, the black ISIS flag was already flying from the roof. Armed men pushed women and children to the second floor. The men were ordered to stay downstairs.

“The last thing I saw of Dad was a terribly sad look he gave me,” Farida writes. “I’ve stored this memory forever in my mind.”

From an upstairs window, Farida watched as all the men were herded into trucks and driven off in different directions.

Within minutes, she heard gunshots.

“You’re killing them!” cried a young mother cradling her baby. “You’re shooting them!”

“Your men are dogs,” an armed soldier replied.

Next, ISIS fighters rounded up Farida’s friends and classmates. Farida herself, who suffered from epilepsy, was literally ripped from her mother’s arms.

They were pushed on to a public bus ISIS had confiscated and driven away.

“We girls were absolutely terrified,” Farida writes. “Some hammered violently against the windows. Others were so desperate that they hit their heads against the glass. They’d rather die than look our future in the eye. We cried the whole journey.”

They arrived in Mosul, now a ghost town with barriers and checkpoints and black flags flying everywhere. They were shoved into a large house packed with young girls, some slapping themselves in hysteria. As the day progressed, 10-year-olds were filed in. The littlest were completely numb.

Nearly two dozen armed men stood guard over the house, and a television was broadcasting news of a massacre in Farida’s hometown — the men, her father. She collapsed in an epileptic fit, and when she came to, her captors threatened to kill her if it happened again.

“You’re all alone in this world,” one fighter told the girls. “You’ve just got us now. We’re your new masters. You are now our property.”

These young girls were now sex slaves, to be used by ISIS fighters or sold or bartered or left for dead. The girls were packed in another convoy and driven over the now non-existent border between Iraq and Syria.

After a ten-hour drive, the convoy approached Raqqa, the Syrian city ISIS had taken as its capital. The girls would now be warehoused in a single-story building behind barbed wire. There was only one window, obstructed with bars.

The next morning, one day after their mass abduction, the girls were given water and cheese sandwiches. Then dozens of new ISIS fighters came in the room.

“They’d frequently reassure each other that they were justified in enslaving us because, as non-Muslims, we were not their equals. As pious Muslims, they were the master race and we were subhumans.”

They were shopping. Farida recognized Iraqi, Syrian, Egyptian, Saudi and Tunisian dialects. One of the guards mentioned that 47 Yazidi girls had just arrived the night before.

“All you new ones, stand together in a group!” he yelled.

They all ignored him. Some of them turned and faced the wall. The girls were dragged to the center of the room and beaten brutally.

“Are all of these girls really still virgins?” one man asked.

“Fresh goods,” replied another.

One approached Farida and stroked her face. Then he touched her face and opened her mouth, to inspect her teeth. She bit down.

“You bitch!” he cried. He began beating her until she convulsed in another epileptic fit. The sight of it caused him to lose interest, which meant Farida would be taken to the slave market in Raqqa.

She’d listen intently as the ISIS fighters talked amongst themselves. “They’d frequently reassure each other that they were justified in enslaving us because, as non-Muslims, we were not their equals,” she writes. “As pious Muslims, they were the master race and we were subhumans.”

The girls had a basin and a little water, but they refused to wash themselves — the filthier and more repulsive they were, the less likely they’d be sold. Farida and her friend Evin were able to stick together, and they’d constantly plot to escape.

They knew that they were about to be raped, but they didn’t really know what rape was. Days later, the girls were dressed in head-to-toe black, as required of all ISIS women, and driven to another safehouse, where they were offered up to more strange men.

Evin was taken upstairs by a Libyan man, and Farida, clutching a bottle of orange juice, was locked in a room downstairs.

“My beloved Evin screamed as if her throat were being slit,” Farida writes. She smashed her bottle of OJ, grabbed a shard of glass and slashed her wrists. To her regret, at that moment, the ISIS guards found her and kept her alive.

Farida’s insurrectionism made her more trouble than she was worth, and after this attempt, her captors shunted her and Evin off to a human trafficker. They were kept, with other Yazidi girls, in a windowless warehouse, never left alone, not even to use the bathroom. They were beaten so badly that at times they could not walk or crawl.

Farida soon realized that the other girls here were her classmates: “Nuhat, our chemistry expert; Revin, our shy class poet; Lavia and Khamia, the life and soul of the playground.”

Within days of Farida’s arrival, Lavia and Khamia were sold into slavery. They were 14 years old.

“Rape as a form of worship”

Zeyad was commander of “The Beasts.” When Farida and Evin were brought before him, shackled, she knew what was next. “I can’t put into words what I felt in that moment,” she writes.

Evin was given to a deputy. Zeyad took Farida. “I observed myself as if from a distance,” she writes, “calmly imagining that the girl enduring all of this only looked like me. I, the real, Farida, was floating above her, where the men couldn’t reach me.”

Yet Farida felt that she’d brought deep shame upon her family, and her only option, again, was suicide. She attempted to strangle herself in her jail cell, but Zeyad found her in time. He then beat her brutally, using an electric cable and barbed pole and blinding her in one eye.

“I think he wanted to kill me,” she writes. “I still bear the scars today.”

Disgusted, Zeyad sold her and Evin to a new band of ISIS soldiers, stationed in a military camp taken from the Free Syrian Army. Again, they were out in the desert, and the head of these marauders had Farida sent to a local hospital, also controlled by ISIS.

There, her hospital door was locked from the outside. She spent 45 days in bed, recovering from Zeyad’s near-fatal beating.

Upon her return to the camp, Farida was given to a soldier, who “rolled out his mat and got ready to kneel down and pray . . . the particularly religious ones commonly did this before taking a woman, thereby celebrating their rape as a form of worship.”

Next, the girls were told they needed to memorize the entire Koran or risk beatings. It was here that Farida truly began plotting her escape: she’d met a 12-year-old girl named Besma, who’d been brutally beaten after attempting to stab her rapist.

“If we can rid ourselves of fear,” Farida told the other girls, “we can do it.”

She and Evin hatched a plan: They’d recently discovered that the door to their container was tied with wire, and Farida was able to slide her arm through a window and unwind it.

So they’d make a break for it in the dead of night, once the guards were drinking, carousing or sleeping. They’d be dressed head-to-toe in black, nearly impossible to see. Not all the girls were convinced to go, but Besma was desperate to get out, preferring to die than remain.

The night of their escape came to them: it was raining, and the noise would shield their footsteps. Farida gathered the girls behind her and unlocked the front door.

“Glancing behind me, I saw the wide, anxious eyes of my friends peeping out from their black veils,” she writes. The girls were two-by-two, holding hands.

The door opened and they ran.

“No future”

Incredibly, Farida, Evin and the girls made their way to a rural house and were taken in by the family who lived there. Another trafficker, this one working for refugees, smuggled the girls to a refugee camp in Iraq, where Farida was reunited with her aunt, uncle and brother.

A few weeks later, her mother escaped the slave market. She’d managed to protect two of her sons from being conscripted by ISIS.

“There’s no future for us in Kocho anymore,” her mother said. When Farida and Evin were offered refugee status in Germany, her mother insisted she go.

“Take this opportunity,” her mother said. “There’s no fresh start here. People are too caught up in their old ways of thinking. And we’ll never make peace with the Muslims.”

Farida and Evin have been living in Germany since last summer, and her mother and brothers soon followed. They all live under special security provided by the government, and Farida dreams of becoming a math teacher.

“I decide that my life will go on, in spite of all the terrors,” she writes. “I won’t give my tormentors the victory of having destroyed it.”